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Open-cell ceramic foams are widely used as filters for the purification of molten metals due to their high permeability and high efficiency for capturing non-metallic inclusions. With the consideration of manufacture and filtration behaviour, most filters are produced by replica methods. The intrinsic multiscale porous structure requires the ceramic foams to have sufficient strength. As a consequence, different processing approaches, material compositions and characterizations are investigated. Meanwhile, to further enhance the filtration performance, the functionalization of ceramic foam filters is often conducted with surface coating. This review summarizes the processing and characteristics of ceramic foam filters (CFFs), the nature and formation of non-metallic inclusions (NMIs), the filtration mechanism and applications of CFFs. The characterization of mechanical and filtration performance, as well as the corresponding strengthening and functionalization methods are also presented.

To widen the understanding of tensile failure of reticulated ceramic foams and expand the available mechanical method, a cylindrical splitting test is developed in the present study based on alumina open-cell foams of three different pore densities. The biaxial method is validated by characterization of mechanical parameters, and the in-situ fracture process is validated by a digital image correlation, followed by a formula correction for effective tensile strength with consideration of discrete crack paths. For experimental setup curved loading platens, compliant pad and intermediate quasi-static loading rate are proposed for guaranteeing tensile failure under a radial compressive load. Tensile strength, fracture energy, and brittleness increase with the foam pore density, and the fracture behavior is a balanced result of materials and foam structural support strength. An analytical model of splitting tensile strength with structural parameters is derived, which implies its dependence on cell size and critical stress intensity factor of strut materials.

The flush air data sensing system is a key or important flight sensor subsystem for the measurement of flight atmospheric parameters such as air pressure altitude, indicated airspeed, Mach number, angle of attack and sideshow angle, which are required for flight safety control, communication and navigation of flying wing pneumatic layout aircraft and precise weapon strike. The effectiveness of water-proof, dust-proof, anti-ice and de-icing design of the flush air data pressure sensor in the system is an important guarantee for accurate pressure feeling, stability of atmospheric parameters and real-time performance during flight. In this paper, aiming at the technology present status of water-proof, dust-proof, anti-icing and de-icing of flush air data pressure sensors in flush air data system, the existing shortcomings and defects are analyzed, combined with the needs of engineering application and research results of related engineering technology, the flush air data pressure sensor for complex meteorological environment protection status online monitoring, heater power adaptive control and rapid disassembling design as development direction is proposed, the future research goal and content of flush air data pressure sensor for complex meteorological environment protection technology are illustrated, and the solutions of key technologies such as moisture monitoring technology, freezing condition monitoring technology, surface hydrophobic and low detectable technology and easy maintenance structure design technology are presented.

Materials that exhibit very small dimensional changes with temperature, i.e., near-zero thermal expansion (NZTE) properties, find attractive prospects in fields such as precision instrumentation and aerospace. However, how to manually design and synthesize NZTE materials with high performance instead of laboriously exploring composition has been a long-standing challenge. In this study, based on the excellent bonding and forming abilities of metallic glass (MG), a composite with continuous regulation of thermal expansion was obtained by combining different volume ratios of MG with beta-LiAlSiO4 (beta-LAS) possessing negative thermal expansion (NTE). Interestingly, excellent NZTE performance of 0.693 and 1.587 ppm/K was achieved over the 150–700 K temperature range when the volume ratio of MG was 40% and 50%, respectively. In addition, the compressive strength of the NZTE composite reached 320 and 436 MPa for the above two ratios, respectively. The thermal shock resistance results show that the composite can withstand thermal cycling tests of not less than 80 times. The proposed strategy not only provides new NZTE materials with high performance but also facilitates a shift in the preparation of high-performance NZTE composites from laborious search to customizable design.

The development of the oxy-fuel porous media combustion technique not only takes advantage of the characteristics of porous media combustion, such as a relatively low lean-burn limit and small volume, but also dramatically facilitates carbon capture and storage. In this paper, a two-layer porous burner model is established, in which a two-temperature equation model is adopted for calculation purposes. Differences in combustion behaviour between oxy-fuel and air-fuel conditions are compared. The results show that the difference in physical properties between CO2 and air is the main reason for the significant variation of combustion behaviours under the conditions of oxy-fuel compared to air-fuel. The specific performance is lower combustion temperature and flame propagation speed. The temperature under oxy-fuel combustion conditions is 300 K lower than that under air-fuel combustion conditions at an equivalence ratio of 0.6, and the stable range of oxy-fuel combustion is only approximately 50% of air-fuel combustion. The impact of porous media material parameters on combustion behavior has been investigated. These variables include the equivalence ratio, material thermal conductivity, volume heat transfer coefficient, and extinction coefficient, while the ratio of O2/CO2 remains fixed at 0.21/0.79. The influence of these variables on the stable velocity range and temperature field is consistent, but a large difference in values occurs. Reducing the thermal resistance of the burner by adjusting the properties of the porous matrix can increase the velocity limit of stable combustion. However, even if the thermal conductivity and extinction coefficient are increased by 5 times, there will be no significant impact on the stable range. Reducing the pore size of the combustion zone by 50% will increase the stable range by over 100%.

Aiming at the low receiving power of space laser communication, a real-time space laser Pulse Position Modulation (PPM) communication system with high receiver sensitivity is designed and implemented in this paper and the transmission rate of this system is 800 Mslot/s. The experimental results show that, after using Erbium Doped Fiber Amplifier (EDFA) and optical filter, under the condition of -58.3 dBm optical input, the Bit Error Rate (BER) of the system before error code correction is 1.4E-4 and the system has ultra-high receiver sensitivity.

The separation of light actinides plays an important role in the fields of nuclear industry, environmental radiochemistry, nuclear forensics, etc. Solid phase extraction(SPE) is one of the main methods for the separation of light actinides, and the key of this method is to select adsorbents with excellent adsorption performance and good physicochemical stability. Porous metal phosphonates are a kind of inorganic-organic hybrid materials combined of metal centers and organic phosphonic acid ligands. Generally, they exhibit high specific surface area, abundant active sites and good physicochemical stability, as well as excellent adsorption properties due to the outstanding binding ability of phosphonic groups to light actinides. Therefore, they are expected to be used as adsorbents for light actinides. In this review, the synthesis and structure of porous metal phosphonates are summarized, and their application in the separation of light actinides is focused, including the adsorption properties, adsorption mechanism, the physiochemical stability and practical treatment methods of these materials, etc. In the end, the development of this field is prospected.

Due to the distinct design concept, high-entropy alloys (HEAs) exhibit unusual properties and lead an emerging new field. In this work, we show that a typical face-centered cubic crystalline phase CoCrFeNiMn HEA can be readily transformed into the amorphous phase under the ultrasonic vibration treatment (UVT) at a frequency of 20000 Hz. The nanoscale hierarchical features include twins, stacking faults bands, hexagonal-close packed phase bands and even amorphous bands can be obviously identified in samples treated by different UVT energies. The dominant mechanism of ultrasonic vibration-induced amorphization is that the grain refinement promotes the formation of amorphous phases when the defect density at the grain boundaries reaches a critical level. In addition, the mechanical instability is easily induced by ultrasonic vibration at high strain rate to generate amorphous phase inside the grains. As a consequence of UVT, the HEA samples revealed significant mechanical performance improvement owing to the microstructure evolution especially the generation of amorphous phase, such as yielding strength and hardness. This rapid amorphization process provides not only a candidate strengthening mechanism for HEA, but also a novel approach to unveil the pending crystal-amorphous transition problem.

In order to solve the problem that the laser satellite terminal can realize the ranging function while completing the communication function, this paper designs a method based on the Delta-Sigma modulation to realize the laser phase ranging, which can integrate the functions of communication and ranging. Multi-frequency point phase ranging is used to balance ranging range and ranging accuracy. Multi-frequency modulation signals are generated using high-speed digital Input and Output (I/O) ports based on Delta-Sigma modulation without any Digital-to-Analog Converter (DAC). Based on the Delta-Sigma modulation method, multiple frequency points for multi-frequency phase ranging can be generated at the same time, which is better than the traditional method of generating each single frequency point separately. Selecting the high frequency of 187.50 MHz and the low frequency of 1.50 MHz, the ranging accuracy can achieve 1 mm in the range of less than 100 m.

RING finger protein 135 has an important role in the occurrence of many cancers; however its regulation and function of RNF135 in hepatocellular carcinoma remains unknown. The promoter methylation status and mRNA expression of RNF135 was evaluated by methylation-specific PCR, semi-quantitative RT-PCR, and real-time quantitative PCR in HCC tissues and cell lines, and further analyzed from The Cancer Genome Atlas database. Wound healing assay, transwell migration, cell viability, and colony formation assay were performed to investigate the function of RNF135. GSEA analysis, TIMER database, and ESTIMATE algorithm were used to decipher the associated pathway and immune infiltration. The survival analysis was applied to assess the prognostic value of RNF135. RNF135 expression was downregulated in HCC tissues and 5 of 8 HCC cell lines, and was negatively correlated with its promoter hypermethylation. Demethylating regent decitabine restored RNF135 expression on the cellular level. Knockdown of RNF135 expression enhanced the migration of HCC cells, while RNF135 overexpression and decitabine treatment repressed cell migration. Bioinformatics analysis and immunohistochemistry revealed a positive relationship between RNF135 expression and six immune cell infiltrates (B cells, CD4+ T cells, CD8+ T cells, neutrophils, macrophages, and dendritic cells). Survival analysis disclosed that RNF135 hypermethylation is independently associated with poor clinical outcomes in HCC. Decreased RNF135 expression driven by promoter hypermethylation frequently occurred in HCC and associated with prognosis of HCC. RNF135 functions as a tumor suppressor and is involved in tumor immune microenvironment in HCC.

In this work, a rapid and controllable ultrasonic vibration method for forming Al-based metallic glass at room temperature is proposed. This method can dramatically improve the forming ability of Al-based metallic glasses, which are virtually brittle at room temperature and have almost no supercooled liquid region at high temperatures. Under ultrasonic vibration, Al-based metallic glasses exhibited obvious plastic flow, with a maximum deformation degree up to 58% and an average deformation degree up to 43%. It is worth mentioning that no crystalline peaks were found on the X-ray diffraction patterns after deformation under ultrasonic vibration, and the mechanical properties remained the same as the primary sample. The present results provide a new approach for the deformation and forming of Al-based metallic glasses, which can significantly broaden their applications.

A hybrid process combining ultrasonic injection molding and electrical discharge machining was proposed to realize the economic, high-precision, and environmental-friendliness production of glass fiber reinforced polypropylene microstructured parts. First, the prism array microstructures were processed on tungsten carbide-cobalt (WC-8 wt% Co) substrate by low-speed wire electrical discharge machining and used as the mold core. Then, the glass fiber reinforced polypropylene composite (GF/PP) was melted under ultrasonic vibration, and the surface microstructure of the mold core was replicated. The experimental results show that this method can efficiently and accurately manufacture microstructured parts, and the microstructure has a high replication rate up to 95.5%. By replicating the microstructure, the surface contact angle of GF/PP parts increased from 57.1° to 134.9°, and the wettability changed from hydrophilicity to hydrophobicity. The mechanical properties test results show that the GF/PP parts fabricated by ultrasonic injection molding had excellent mechanical properties, and the 30% GF/PP parts show the highest tensile strength of 56.9 MPa. This work provides a new option for fabricating fiber reinforced composite parts.

Despite the excellent properties, amorphous alloys find limited applications and to find plastic forming ability has been a longstanding problem. In this work, an effective ultrasonic assisted micro-shear punching (UMSP) method is proposed for amorphous alloys. By applying ultrasonic vibration and molten plastics viscous medium, a series of shapes and products with micro-length scale to macro-length scale can be successfully fabricated in 50 ms. Different from traditional crystalline alloys, the amorphous alloys become soft at certain regions during the ultrasonic hammering owing to the unique disordered structures, thereby resulting in the low-stress forming approach.

Mullite reticulated porous ceramics (RPC) are one of the key components for porous media burner, the mechanical properties of mullite RPC decided the service life of the burner. However, the irregularities of cellular structure made it difficult to reveal the fracture behavior of mullite RPCs. In this study, the three-dimensional (3-D) structures of mullite RPCs were analyzed by X-ray computed tomography. The strength and damage behavior of mullite RPCs were respectively investigated via the compression tests and finite element modeling based on the actual 3-D model, also the corresponding strengthening mechanism was proposed. The results indicated that the reconstructed 3-D model exhibited the real microstructure of mullite RPCs, containing the hollow struts and strut defects. The Young's modulus calculated from actual 3-D structures was lower than that from Gibson-Ashby theory. In addition, the surface defects preceded triangular tips to generate the area of stress concentration, leading to the fracture behavior first occurred at the strut defects. With the formation of dense strut in mullite RPCs, the stress uniformly distributed in the whole solid skeleton, thus significantly improving the damage resistance of mullite RPCs.

To investigate the optimal longitudinal seismic energy dissipation system of straddle-type monorail-cum-road long-span cable-stayed bridges, the Niutianyang Bridge was selected as the engineering background, and the explicit time-domain dimension-reduced iteration method was adopted to carry out nonlinear time-history analysis. To consider the dynamic characteristics of longitudinal movable supports, the static and dynamic responses of four kinds of energy dissipation systems were studied, including longitudinal unconstrained, elastic cable, viscous damper, and speed lock-up devices. The damping effect of four types of schemes in which viscous dampers were installed at piers or towers was analysed, and the parameters of the viscous dampers were optimised. The influences of the straddle-type monorail train braking force and the running vibration of the straddle-type monorail traffic on the parameters of the viscous dampers were analysed. This study shows that the viscous damper system had the lowest bending moment at the bottom of the tower and a smaller displacement response, and the energy dissipation was the best. Each viscous damper had the highest energy dissipation efficiency when they are installed only at the main tower. The damping effect was better when the damping coefficient c ranged from 3500 to 5000 kN⋅m/s−α and the velocity exponent α ranged from 0.35 to 0.5. The static friction of the straddle-type monorail-cum-road long-span cable-stayed bridge support can resist the trains’ braking force, and the parameters of the viscous damper can be selected regardless of train braking. A suitably large value of velocity exponent α may be required to increase the working velocity of the viscous damper to reduce the damper’s participation in the process of the train crossing the bridge.

Constructing regular micro-structures with certain geometric characteristics on the surface of the polymer part can obtain some specific functions. Micro ultrasonic powder molding (micro-UPM) is an efficient processing technique for the fabrication of well-filled micro-structured Polypropylene (PP) parts. The micro-structure array on the surface of the core insert was obtained by low speed wire electrical discharge machining (WEDM-LS). PP polymer surfaces with micro-structured patterns were successfully replicated from the core insert surface after micro-UPM. By studying the detailed topography characterizations of micro-structured PP parts, the effects of processing parameters (ultrasonic energy, welding pressure and holding time) on the micro-structured filling show that when PP polymer was formed under the conditions of 1000 J, 115 kPa and 8 s during micro-UPM, well-filled micro-structured parts can be obtained. Besides, without low surface energy coating modification, the water contact angles (WCAs) of micro-structured PP parts increased from 85.3° to 146.8°, indicating that the wettability of the surface can be changed by replicating the micro-structure on PP parts after micro-UPM.

To assess if the maternal pre-pregnancy weight status (MPWS) alters the association of early infant feeding pattern (at one and third months) with infant body mass index (BMI) in the first two years of life.A cohort of 2,220 neonates were recruited in a community-based study conducted in China. Body weight and length were measured at birth, at age one and two, with BMI calculated accordingly. The BMI z-scores (BMI-Z) were computed according to the World Health Organization Growth Standard (2006). Feeding patterns were classified as exclusive breastfeeding (EBF), mixed feeding (MF), and formula feeding (FF). General linear models (GLM) were employed to estimate main and interaction effects of EBF and MPWS on children's BMI-Z.No main effect of MPWS was found on child BMI-Z at ages one and two, nor the feeding patterns. An interaction between MPWS and feeding patterns was detected (p