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Bulk metallic glasses (BMGs) display excellent strength, high hardness, exceptional wear resistance and corrosion resistance owing to its amorphous structure. However, the manufacturing of large-sized and complex shaped BMG parts faces significant difficulties, which seriously hinders their applications. Laser powder bed fusion (LPBF) is a typical additive manufacturing (AM) technique with a cooling rate of up to 108 K/s, which not only allows for the formation of amorphous structures but also solves the forming problem of complex-shaped BMG parts. In recent years, a large amount of work has been carried out on the LPBF processing of BMGs. This review mainly summarizes the latest progress in the field of LPBF additively manufactured BMGs focusing on their mechanical properties. We first briefly review the BMG alloy systems that have been additively manufactured using LPBF, then the mechanical properties of LPBF-fabricated BMGs including the micro- and nano-hardness, micropillar compressive performance, and macro-compressive and tensile performance are clarified. Next, the relationship between the mechanical properties and microstructure of BMGs produced via LPBF are analyzed. Finally, the measures for improving the mechanical properties of LPBF-fabricated BMGs are discussed. This review can provide readers with an essential comprehension of the structural and mechanical properties of LPBF-manufactured BMGs. [ABSTRACT FROM AUTHOR]

Summary: The metro‐induced vibrations and seismic safety are both big issues for historical buildings in modern cities. This paper proposed a novel hybrid vibration bearing (HVB) to isolate horizontal earthquakes and mitigate vertical metro‐induced vibrations. The HVB consists of lead rubber bearing and thick rubber bearing with decoupled horizontal and vertical behaviors. The mechanical model of HVB is developed, and a new vertical stiffness formula of thick rubber bearing is proposed to calculate the compression stiffness, without conducting test. A static test of the prototype HVB and a dynamic experiment of an SDOF system were performed. The bearing has stable behavior under different pressures and lateral deformations. The bidirectional test confirmed the decoupling characteristics. The isolation design and retrofitting of an overtrack historical building was conducted. After retrofitting, the average maximum vibration level and the average subfrequency vibration level decreased 25% and 18%, respectively. The horizontal accelerations of isolated structure were 65% to 70% of the input, and the shear strains of bearings were smaller than 200% under rare earthquakes. Finally, case study of structures with different types of foundations is introduced. The vibration mitigation efficiency of different structures is confirmed. [ABSTRACT FROM AUTHOR]

Laser powder bed fusion (LPBF) technology presents significant potential for the production of metallic glass (MG) coatings. This work investigated the influence of laser power on the structure and wear performance of a CuZr-based metallic glass coating with composition of Cu 45 Zr 45 Al 6 Ti 4 on Ti substrate. It was observed that the melt pool, which serves as the fundamental building block for constructing MG coatings in LPBF, undergoes a transition from conduction mode to keyhole mode, and subsequently to extended mode with increasing laser power. The MG coatings prepared using low power laser (140 W) and medium power laser (240 W) both exhibited a nearly fully amorphous state. However, at a laser power of 360 W, noticeable crystallization occurred in the coating, as evidenced by SEM observation. The wear rate of Cu 45 Zr 45 Al 6 Ti 4 MG coating was measured to be 4.67 × 10−6 mm3·N−1·m−1, which is significantly lower than that of the Ti substrate (6.38 × 10−4 mm3·N−1·m−1). This study reveals the relationship between the laser power and morphology of the melt pool, as well as the structure and wear performance of the LPBF-fabricated MG coatings, offering guidance for optimizing the laser additive manufacturing process of wear-resistant MG coatings. [Display omitted] • Melt pool in MG changes from conductive to keyhole, then to extended mode with increasing laser power. • A strategy to optimize LPBF parameters for MG coatings based on melt pool characteristics is proposed. • Keyhole melt pool can promote formation of amorphous structure with low porosities in MG coatings. • Cu 45 Zr 45 Al 6 Ti 4 MG coating shows 136 times higher wear resistance than the Ti substrate. [ABSTRACT FROM AUTHOR]

[Display omitted] • A Ti-Si-O ternary film is constructed for dual-spectrum bands compatibility. • The electromagnetic properties can be regulated by adjusting element contents. • A structure with TiO grains surrounded by amorphous region is in-situ obtained. • The Ti-Si-O film realizes low infrared emissivity and high microwave transmittance. Military stealth places higher demands on dual-band electromagnetic wave response in the infrared and microwave bands, and an outer layer with both low infrared emissivity and high microwave transmittance is required for multi-layer compatible stealth materials. In this work, a series of Ti-Si-O films were prepared by magnetron co-sputtering and annealing as the outer layer. The infrared emissivity and microwave transmittance of as-deposited films increase gradually with the decrease of Ti content. After annealing, the microwave transmittance increases obviously due to the occurrence of Ti-O reaction, and only the film with a Ti/Si ratio of ∼7/1 can maintain a low infrared emissivity. In the optimized film, microwave-transparent TiO grains are generated while original electrically conductive amorphous region still exists and surrounds around TiO, which makes it have both a low average infrared emissivity of 0.32 in infrared band from 2.5 to 25 μm and a high average transmittance of 88.5% in microwave band (2.42–3.66 cm). [ABSTRACT FROM AUTHOR]

The inherently advantageous geographical location of East and Southeast Asia provides a great potential for the development of diverse ocean energy technologies along its densely populated coastlines. This review paper focuses on the flexibility and feasibility of emerging ocean energy technologies in this region, including wave, tidal and ocean-current energy converters, floating photovoltaics, and offshore wind-turbines. Recent research on wave energy in the region has achieved advancements such as modifying oscillating water columns to exchange higher pneumatic energy, reshaping oscillating devices to capture more kinetic energy, and improving overtopping converters to absorb more incident waves. Regarding tidal energy, the paper reviews barrage-based and stream-based turbines and investigates the efficiency improvement, flexibility enhancement and adaptation to the unique regional features. Regarding ocean current energy, research on low-velocity turbines and optimized energy storage systems has made their application in the region more competitive. In addition, offshore deployments of floating photovoltaics have recently drawn the sector's attention and are beginning to emerge in the region, although their robustness against extreme weather and wave conditions should be addressed. Furthermore, compared to other ocean technologies, offshore wind technologies have attracted the most investment in the region. Due to the fluctuation of wind-energy generation, enhancing the energy flexibility to increase its grid penetration has become a recent focus in both the academic and industrial communities. However, despite the good research and demonstrations, most of the abovementioned ocean technologies still encounter considerable techno-economic and techno-environmental challenges that limit their competitiveness in the East and Southeast Asian markets. • State-of-the-art review of advanced ocean energy technologies for Asian Regions. •Regional ocean energy review regarding energy flexibility potential and challenge. •Recent progresses and ocean energy potentials in East and Southeast Asia. •Future development and challenges of ocean energy in East and Southeast Asia. •Ocean energy applications in the densely-populated coastal regions and challenges. [ABSTRACT FROM AUTHOR]

In this paper, in order to study the dynamic behavior of the three-body interaction, the generalized Kuramoto model with bimodal frequency distribution under the joint interaction of two-body and three-body is proposed. The comparative numerical results of the phase synchronization paths of the three-body interaction under different coupling strengths show that the three-body interaction can transform the continuous transition process into the first-order transition process. Interestingly, the change from continuous to discontinuous transition due to the variation of the coupling strength of the three-body interaction is similar to the shape of the bimodal distribution of the natural frequency. The critical coupling strength of the two-body interaction of synchronous transition is derived from the Ott–Antonsen–Ansatz method. The numerical results are consistent with the theoretical ones. The findings help our understanding of the transformation process from being continuous to discontinuous. [ABSTRACT FROM AUTHOR]

Nano‐heterointerface engineering has been demonstrated to influence interfacial polarization by expanding the interface surface area and constructing a built‐in electric field (BEF), thus regulating electromagnetic (EM) wave absorption. However, the dielectric‐responsive mechanism of the BEF needs further exploration to enhance the comprehensive understanding of interfacial polarization, particularly in terms of quantifying and optimizing the BEF strength. Herein, a “1D expanded 2D structure” carbon matrix is designed, and semiconductor ZnIn2S4 (ZIS) is introduced to construct a carbon/ZIS heterostructure. The cross‐dimensional nano‐heterointerface design increases interface coupling sites by expanding the interface surface area and induces an increase in the Fermi level difference on both sides of the interface to modulate the distribution of interface charges, thereby strengthening the BEF at the interface. The synergistic effect leads to excellent EM absorption performance (minimum reflection coefficient RCmin = −67.4 dB, effective absorption bandwidth EAB = 6.0 GHz) of carbon/ZIS heterostructure. This work introduces a general modification model for enhancing interfacial polarization and inspires the development of new strategies for EM functional materials with unique electronic behaviors through heterointerface engineering. [ABSTRACT FROM AUTHOR]

Background: To investigate the clinical significance of ubiquitin-specific peptidase 19 (USP19) expression in gastric cancer (GC) compared with that in normal tissues and gastric cell lines. Methods: USP19 protein expression was analyzed in 212 paired GC samples using immunohistochemical staining. Quantitative real-time PCR (qRT-PCR) and Western blotting were used to detect the level of USP19 in gastric cell lines. The biological functions of USP19 were investigated by MTT assay, colony-forming assay, wound healing assay and gelatin zymography, and apoptotic cells were detected by immunohistochemistry assays in SGC7901 xenograft models. Results: USP19 expression was significantly increased in GC cells and tissues, and the high level of USP19 expression was positively correlated with the Lauren's classification and poor prognosis. Moreover, USP19 was identified as a novel independent prognostic biomarker in GC patients. Enhanced USP19 expression promoted GC cell proliferation and metastasis through reduced cleaved caspase-3 and increased MMP2/MMP9 expression and promoted enzyme activity in the study, and verified the results through The Cancer Genome Atlas (TCGA) and bioinformatic websites from the Kaplan–Meier plotter (http://kmplot.com) and GEPIA (http://gepia2.cancer-pku.cn.). Conclusion: Our study suggests that USP19 promoted tumor progression by inducing MMP2/MMP9 expression and related enzyme activity. Hence, USP19 may be a valuable prognostic predictor for GC, and the USP19-MMP2/MMP9 axis could serve as a therapeutic target. [ABSTRACT FROM AUTHOR]

The effects of acidification reduction on methane (CH4), ammonia (NH3) and hydrogen sulphide (H2S) emissions from digested pig slurry during storage were investigated. Pilot-scale experiments designed with three different pH levels including one control and two acidified treatments were conducted. Digested pig slurry was stored and tested in nine mechanically ventilated reactors. An online and continuous monitoring system was used to acquire gas emissions data during the whole storage period. Temperatures and pH in digested slurry were continuously measured with sensors. Off-gas from the reactors and air from room environment were sampled alternately then supplied to gas analysers for CH4 and H2S determination. Headspace NH3 from the 9 reactors were regularly sampled by an air sampling instrument and then determined for concentration by spectrophotometer. The study found that digested pig slurry characteristics still didn't satisfy the national standards after 95 days treatments. Both temperature and pH were crucial factors to influence CH4 and NH3 emissions from digested pig slurry. In the control group (Gn) CH4 and H2S emissions mainly occurred in the first 20 days and 12 days, respectively; while no predictable NH3 emission patterns were found in the experiment. Comparing with Gn, adjustment of initial pH to 5.5 significantly reduced CH4 emissions by 80.8% and NH3 emissions by 40.2%, but increased H2S emissions by 11,324% (average increasing emission flux was 4.1 μg m−2 min−1). Acidification with pH adjusted to 6.5 reduced CH4 emissions by 31.2%, but did not affect NH3 and H2S emissions significantly. [ABSTRACT FROM AUTHOR]