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In a time characterized by the increasing interest in metal–organic frameworks (MOFs) as widely researched crystalline porous substances geared toward enhancing device and system capabilities across diverse environmental contexts, 2D MOFs emerge as a noteworthy class of nanomaterials that integrate the benefits of 2D structures with the unique characteristics inherent to MOFs. These 2D MOFs possess ultrathin nanosheet configuration, abundant accessible active sites, and remarkable mechanical flexibility. Such distinctive properties differentiate them from bulk MOFs and other 2D materials, offering the potential to instigate novel environmental phenomena and applications. This review focuses on the latest progress in the application of 2D MOFs within essential water‐related ecological fields, including contaminant adsorption, photocatalytic degradation, membrane separation, environmental sensing, and disinfection. A variety of synthesis approaches for 2D MOFs are analyzed, accompanied by a discussion on their effectiveness across different environmental settings. The unique structure and features of 2D MOFs that grant outstanding environmental functionalities are compared with those of bulk MOFs. The environmental ramifications of 2D MOFs are highlighted while outlining future research needs to explore the environmental applications of these innovative materials. [ABSTRACT FROM AUTHOR]

Porous one-dimensional Pt-based alloys with outstanding specific surface areas, short electron transport paths, and accessible Pt atoms are potential electrocatalysts for methanol oxidation reaction (MOR); however, their simple one-step synthesis for MOR remains a challenge. In this study, a simple one-step method is presented for the rational fabrication of PtPb porous nanowires (PNWs) by the direct autoclave of binary metal precursors in the mixed solvent of ethylene glycol and N,N -dimethylformamide at 170 °C. The formation of PtPb PNWs is driven by the autocatalytic and Ostwald ripening growth mechanism with the assistance of ethylene glycol and N,N -dimethylformamide as a solvent, in situ template, and reducing agent. This method forms PtPb porous ultra-long (∼1.5 μm) neural PNWs with an average width of 20 nm enriched with abundant pores (5–10 nm), high Pb content (29 wt%), and decreased d-band level of Pt. These unique structural features enhanced the MOR mass (specific) activity of PtPb PNWs of 4.39 mA/μg Pt (49.3 mA/cm2) by 4.5 (9.6) and 5.5 (35.0) times than those of Pt PNWs and Pt/C catalyst, respectively besides higher durability and CO-tolerance. The MOR activity of PtPb PNWs was among the highest reported binary porous Pt-based catalysts, which may promote the preparation of other Pt alloys PNWs for MOR. [Display omitted] • Porous PtPb neural nanowires (PNWs) were prepared by a simple one-step method. • The formation mechanism of PtPb PNWs was underlined using various analyses. • The methanol oxidation performance of PtPb PNWs was superior to other PtPb. • The mass activity of PtPb PNWs was higher than Pt PNWs and Pt/C catalysts. [ABSTRACT FROM AUTHOR]

The advancement of military technology, 5G communication, and electronic equipment has increased the demand for efficient electromagnetic wave absorption materials. Calcium manganate (CaMnO 3) is a commonly used dielectric absorber due to its excellent dielectric polarization effect. However, traditional ceramic materials like CaMnO 3 have low conductivity, making it difficult to achieve impedance matching and electromagnetic loss simultaneously. In this work, to address this issue and create ideal wave-absorbing materials, one-dimensional La-doped CaMnO 3 materials were synthesized using a simple biological template hydrothermal method. By studying the relationship between doping content and electromagnetic parameters, it was found that the La-doped CaMnO 3 material exhibited excellent electromagnetic wave absorption properties, with a minimum reflection loss (RLmin) of −73.62 dB and a maximum effective absorption bandwidth of 3.3 GHz in the X-band. The introduction of La elements, which have different electronegativities from Ca ions, altered the electron cloud distribution in the sample, leading to the formation of electric dipoles that disrupt charge distribution and dissipate electromagnetic waves. The dielectric loss in fibrous La-doped CaMnO 3 is mainly due to interfacial polarization. The fibrous structure allows for increased contact area with the air medium, while the porous structure introduces air bubbles that alter the dielectric properties between the sample and the air medium. This not only enhances impedance characteristics to some extent but also triggers interfacial polarization. Both of these factors help improve the material's ability to absorb electromagnetic waves. The successful creation of this one-dimensional absorbing material opens up possibilities for developing new one-dimensional absorbing materials using a straightforward method. [ABSTRACT FROM AUTHOR]

Schematic illustration of the fabrication processes of NYCs samples under different pyrolysis temperature. [Display omitted] The energy storage capacity of porous carbon materials is closely tied to their surface structure and chemical properties. However, developing an innovative and straightforward approach to synthesize yolk-shell carbon spheres (YCs) remains a great challenge till date. Herein, we prepared a series of porous nitrogen-doped yolk-shell carbon spheres (NYCs) via a "pyrolysis-capture" method. This method involves coating the resorcinol–formaldehyde (RF) resin sphere with a layer of compact silica shell induced by 2-methylimidazole (ME) catalysis to produce a confined nano-space. Based on the confined effect of compact silica shell, volatile gases emitted from the RF resin and ME during pyrolysis can not only diffuse into the pores of the RF resin but can also be captured to form an outer carbon shell. This results in the tunable structures of NYCs materials. As the pyrolysis temperature rises, the shell thickness of NYCs reduces, the pore size expands, the roughness increases, and the N/O content of surface elements is enhanced. Notably, as an electrode material used for supercapacitors, the optimized NYCs-800 exhibits excellent performance with a capacitance of 301.2F g−1 at the current density of 1 A/g and outstanding cycling life stability of 96.1% after 10,000 cycles. These results signify that controlling the surface structure and chemical properties of NYCs materials is an effective approach for constructing advanced energy storage materials. [ABSTRACT FROM AUTHOR]

Freeze casting is a solidification technique utilized in the fabrication of porous materials. However, the freeze casting process is quite complex, and significant challenges remain in precisely controlling the pore size and shape of porous structures. This study aims to investigate the customization of multifunctional electromagnetic wave (EMW) absorbers with 3D porous structures via freeze casting. This review initially presents the fundamental principles underlying the freeze casting technique and examines the correlation between internal and external factors during the preparation process and porosity. The emerging trends in constructing novel and intricate macroscopic structures through freeze casting are subsequently outlined. Furthermore, this review focuses on the fabrication of composites with various porous microstructures through freeze casting of low‐dimensional building blocks, and their EMW response and multifunctional properties. By regulating the internal and external influencing mechanisms of freeze casting, porous EMW absorption materials exhibit outstanding advantages such as electromagnetic property manipulation, controllable structure, high porosity, high specific surface area, lightweight, and flexibility. These features broaden their applications in electromagnetic shielding, mechanical property, radar stealth, thermal insulation and fire prevention, flexible sensors, antifreeze ability, etc. In addition, we discuss the challenges and prospects of high‐performance EMW absorbers using freeze casting techniques. [ABSTRACT FROM AUTHOR]

The sodium‐ion batteries (SIBs) are expected to be the substitute for lithium‐ion batteries (LIBs) because of their low cost, high abundance, and similar working mechanism. Among them, polyanion‐type electrodes show great application prospects due to their superior ion diffusion channels and structural stability. However, there are still many scientific issues that need to be thoroughly investigated, especially the formation mechanism, structural stability, and interface impedance of solid–liquid interfaces. Therefore, it is of great significance to systematically study the mechanism of interface reaction and the electrochemical behavior, to promote the further practical application of SIBs. Fortunately, the polyanionic electrodes can effectively improve the transport dynamics and the interfacial stability of the solid–liquid interfaces through constructing the porous structure, surface modification, and electrolyte strategies, thus improving the cycle and rate performance. This review discusses the characteristics and formation mechanisms of electrode/electrolyte interface (EEI), as well as their electrochemical behavior in porous structures with different dimensions. Furthermore, this review covers the application of porous materials in improving transport kinetics and EEI. In particular, it highlights the various strategies employed to comprehend the interplay among structure, chemistry, preparation methods, and the mechanisms of porous electrodes that ultimately affect the electrochemical properties of SIBs. [ABSTRACT FROM AUTHOR]

Electrolyzing seawater to produce hydrogen is a promising sustainable energy production technology. The current non-precious metal-based hydrogen evolution reaction (HER) electrocatalysts demonstrate inadequate catalytic activity and poor stability in seawater electrolyte. Therefore, developing stable and efficient non-precious metal-based HER electrocatalysts is a major challenge for achieving sustainable green energy development. This work reports a multi-component intermetallic catalyst FeCoCuAlMo prepared by arc melting and chemical dealloying methods. The electrocatalytic hydrogen evolution performance of catalysts with varying atomic ratios (FeCoCu) 20 (Al 70 Mo 30) 80 , (FeCoCu) 30 (Al 70 Mo 30) 70 , (FeCoCu) 40 (Al 70 Mo 30) 60 , and (FeCoCu) 50 (Al 70 Mo 30) 50 in alkaline seawater and alkaline electrolyte was studied. The findings indicate that these catalysts primarily consist of AlMo 3 and (Cu 0.35 Fe 0.35 Co 0.3)Al, among which the dealloyed (FeCoCu) 30 (Al 70 Mo 30) 70 exhibits excellent catalytic activity with overpotentials of 137.54 and 116.91 mV at a current density of 100 mA/cm2 in alkaline seawater and alkaline electrolyte, respectively, outperforming most catalysts. Additionally, it demonstrated long-term stability in alkaline seawater and alkaline electrolyte for 250 and 400 h without significant decay at overpotentials of 236 mV and 276 mV, respectively. This improved performance can be attributed to the unique structure of the multi-component intermetallic compound, which provides good thermodynamic stability and synergistic effects among its constituents, thereby enhancing HER performance. Within this multi-component intermetallic compound, AlMo 3 particles serve as the primary conductive medium to accelerate electron transfer, while (Cu 0.35 Fe 0.35 Co 0.3)Al serves as the main active site, resulting in a stable structure that provides the catalyst with high catalytic activity and good stability. Thus, the (FeCoCu) 30 (Al 70 Mo 30) 70 electrocatalyst is a promising candidate for seawater electrolysis aimed at hydrogen production. [Display omitted] • Intermetallic composed of AlMo 3 , Al 5 CuMo 2 , and (Cu 0.35 Fe 0.35 Co 0.3)Al was prepared. • AlMo 3 and (Cu 0.35 Fe 0.35 Co 0.3)Al provide pathways and active sites for the catalyst. • It exhibited an overpotentials of 137.54 mV at 100 mA/cm2 in alkaline seawater. • The catalyst shows excellent durability at overpotentials of 276 mV for 400 h. [ABSTRACT FROM AUTHOR]

High-frequency noise exceeding 1 kHz has emerged as a pressing public health issue in industrial and occupational settings. In response to this challenge, the present study explores the development of a graphene oxide–polyethyleneimine (GO-PEI) foam (GPF) featuring a hierarchically porous structure. The synthesis and optimization of GPF were carried out using a range of analytical techniques, including Raman spectroscopy, scanning electron microscopy (SEM), Braunauer–Emmett–Teller (BET) analysis, X-ray diffraction (XRD), and Fourier-transform infrared spectroscopy (FT-IR). To evaluate its acoustic properties, GPF was subjected to sound absorption tests over the 1000–6400 Hz frequency range, where it was benchmarked against conventional melamine foam. The findings demonstrated that GPF with a GO-to-PEI composition ratio of 1:3 exhibited enhanced sound absorption performance, with improvements ranging from 15.0% to 118%, and achieved a peak absorption coefficient of 0.97. Additionally, we applied the Johnson–Champoux–Allard (JCA) model to further characterize the foam's acoustic behavior, capturing key parameters such as porosity, flow resistivity, and viscous/thermal losses. The JCA model exhibited a superior fit to the experimental data compared to traditional models, providing a more accurate prediction of the foam's complex microstructure and sound absorption properties. These findings underscore GPF's promise as an efficient solution for mitigating high-frequency noise in industrial and environmental applications. [ABSTRACT FROM AUTHOR]

From a char of Palm seed (CSP), activated carbon at 973, 1073, and 1173 K was obtained (CASPs). These temperatures developed textural properties to favor the adsorptive properties. The CASPs percentage of burning decreased with the increase of the activation temperature from 76 to 26%. These products were obtained with a CO2 flow (as activating gas) and a short time of activation. The CASPs were characterized by mercury porosimetry, adsorption of N2, CO2, and methylene blue at 77, 273, and 298 K, respectively. Wide supermicropores were obtained for CASP1173 and narrow mesoporosity was achieved for CASP973 and CASP11073 (1.4–2.0 nm and 2.0–5.0 nm, respectively). Mercury porosimetry determined that the activated carbons have mesopores with diameters smaller than 50 nm and macropores with diameters greater than 50 nm. The use of Dubinin and Langmuir models showed that the adsorption occurred in the larger diameter micropores and smaller diameter mesopores of the highest and shortest diameters (above 3.85 mmol/g). The activated carbon at 973 K showed a higher methylene blue adsorption capacity (181.03 mg/g). The MB adsorption was determined by the diameters of the adsorbent pores. For this reason, a batch adsorption system to remove this contaminant was proposed. [ABSTRACT FROM AUTHOR]

Direct ink writing (DIW) technology supersedes traditional mold‐based forming methods, significantly enhancing the fabrication of personalized and customized products with complex structures. This technology particularly excels in achieving precise control over the porosity of porous constructs. This study employs inorganic Al2O3 as raw material, sodium hexametaphosphate as dispersing agent, and inorganic SiO2 micropowder as binding medium to fabricate lattice porous structures. One challenge encountered is the viscoelastic behavior of the extruded filament. When spanning the unsupported segments of the lower layer, the upper extruded filaments are susceptible to deflection or collapse, adversely affecting the porosity and dimensional fidelity of the final specimens. Experimental results revealed that a larger span and smaller modulus will cause the extruded filament to be more prone to deformation at the midpoint. The introduction of 2 wt% polyethylene glycol as a plasticizer mitigates this issue, ensuring nondeflection of the extruded filaments at a span of 6 mm. The deflection model for the extruded filament about span and modulus identifies the minimum modulus necessary to prevent or minimize deflection under given spans, which closely approximates our experimental findings, offering a valuable framework for guiding the production of high‐precision, porosity‐controlled porous structures. [ABSTRACT FROM AUTHOR]

背景：假体松动和磨损是导致全踝关节置换失败的主要原因, 其与骨-植入物界面的微运动、关节面的接触应力和关节运动密切相关。包 括衬垫和胫/距柄假体在内的人工关节部件的设计构造是影响踝关节受力、运动、接触界面微运动的关键因素, 开发新型衬垫对提高人工 踝关节生存率具有重要意义。 目的：构建全踝关节置换有限元模型用以检测多孔结构优化型衬垫的生物力学特性, 分析多孔结构优化型衬垫在减少假体微动和改善关节 面接触行为方面的作用。 方法：以一名健康成年人右踝关节CT扫描数据和INBONE Ⅱ系统产品手册为基础, 建立包括骨骼和人工关节系统的三维模型, 在经过截骨 和假体安装后获得全踝关节置换模型(模型A), 再通过对原始衬垫进行多孔结构改造获得G50型、G60型、D50型、D60型4种新型衬垫, 将 不同衬垫替换原始衬垫以建立与之相对应的优化型全踝关节置换模型(模型B-E), 在5个模型上施加步态载荷模拟步态工况。比较5种模型 植入物-骨界面微动和关节面接触行为的差异。 结果与结论：①在步态周期下4个优化型全踝关节置换模型的假体微动小于原始模型, 与模型A相比, 模型B-E假体微动数值上分别下降 5.4%, 10.1%, 8.1%及20.9%, 再者优化型模型在胫骨骨槽穹顶部的高微动区域较原始模型明显缩小；②4个优化型模型获得了更大的关节 面接触面积, 与模型A相比, 模型B-E衬垫接触面积均值分别增加了11.8%, 14.7%, 8.1%及32.6%；③与接触面积增大的效果类似, 相较于 原始模型, 优化型模型的关节面接触应力不同程度下降, 其中模型E的数值下降最为显著(P < 0.05), 归功于构成D60型衬垫Diamond晶格良 好的力学属性和较大的孔隙率；④结果表明全踝关节置换使用多孔结构改良衬垫可以提高衬垫的弹性, 增加其吸收关节冲击力的能力, 为 降低植入物-骨界面微动和改善关节接触行为创造有利条件。 [ABSTRACT FROM AUTHOR]

Based on the advantages of triply periodic minimal surface (TPMS) porous structures, extensive research on NiTi shape memory alloy TPMS scaffolds has been conducted. However, the current reports about TPMS porous structures highly rely on the implicit equation, which limited the design flexibility. In this work, novel shell-based TPMS structures were designed and fabricated by laser powder bed fusion. The comparisons of manufacturability, mechanical properties, and shape recovery responses between traditional solid-based and novel shell-based TPMS structures were evaluated. Results indicated that the shell-based TPMS porous structures possessed larger Young's moduli and higher compressive strengths. Specifically, Diamond shell structure possessed the highest Young's moduli of 605.8±24.5 MPa, while Gyroid shell structure possessed the highest compressive strength of 43.90±3.32 MPa. In addition, because of the larger specific surface area, higher critical stress to induce martensite transformation, and lower austenite finish temperature, the Diamond shell porous structure exhibited much higher shape recovery performance (only 0.1% residual strain left at pre-strains of 6%) than other porous structures. These results substantially uncover the effects of structural topology on the mechanical properties and shape recovery responses of NiTi shape memory alloy scaffolds, and confirm the effectiveness of this novel structural design method. This research can provide guidance for the structural design application of NiTi porous scaffolds in bone implants. [ABSTRACT FROM AUTHOR]

Effective intratumoral drug penetration is pivotal for successful cancer treatment. However, due to the disrupted capillary networks and poor perfusion in solid tumors, there exist challenges to realize autonomous directional drug penetration and controlled drug release within the tumor. Considering the specificity of glucose within tumor tissue, we draw inspiration from nature and engineer asymmetrical hollow structures exhibiting chemotaxis towards high glucose levels. By incorporating multiple shells into these structures, we enhance the local chemical concentration gradients, thereby improving cellular uptake and precise targeting. The advantages of anisotropic hollow multishell structure (a‐HoMS) can be reflected from the diffusion coefficient and directivity, which increase by 73.4 % and 273 % respectively compared to conventional isotropic hollow spheres, achieving the most linear movement while ensuring the speed of movement. Furthermore, the multi‐level porosity and temporal‐spatial order of a‐HoMS enable sequential drug delivery that inhibits angiogenesis with inducing cell apoptosis. After the eradication of localized tumor cells, the a‐HoMS can automatically migrate to the alive tumor cells under the glucose gradient, inducing another cycle of drug delivery and chemotaxis, resulting in excellent antitumor efficacy. These anisotropic HoMS demonstrate intelligence, adaptability, and precision in tumor therapy, providing valuable insights for programmable treatment within tissues. [ABSTRACT FROM AUTHOR]

In this study, a novel bionic periosteum (BP)‐bioactive glass fiber membrane (BGFM) is designed. The introduction of magnesium ion (Mg2+) and zinc ion (Zn2+) change the phase separation during the electrospinning (ES) jet stretching process. The fiber's pore structure transitions from connected to closed pores, resulting in a decrease in the rapid release of metal ions while also improving degradation via reducing filling quality. Additionally, the introduction of magnesium (Mg) and zinc (Zn) lead to the formation of negative charged tetrahedral units (MgO42− and ZnO42−) in the glass network. These units effectively trap positive charged metal ions, further inhibiting ion release. In vitro experiments reveal that the deigned bionic periosteum regulates the polarization of macrophages toward M2 type, thereby establishing a conducive immune environment for osteogenic differentiation. Bioinformatics analysis indicate that BP enhanced bone repair via the JAK‐STAT signaling pathway. The slow release of metal ions from the bionic periosteum can directly enhance osteogenic differentiation and vascularization, thereby accelerating bone regeneration. Finally, the bionic periosteum exhibits remarkable capabilities in angiogenesis and osteogenesis, demonstrating its potential for bone repair in a rat calvarial defect model. [ABSTRACT FROM AUTHOR]

Tricalcium silicate (C3S) is one of the main components of mineral trioxide aggregates, which is used in dental endodontic treatment. C3S provides workable viscosity itself and fast hydration when water is added, and it is known to be nontoxic, noncarcinogenic, nongenotoxic, biocompatible, and insoluble in tissue fluids. In this study, C3S is added to synthetic bone‐graft materials from 30% to 60% to deliver viscosity to increase workability in the early stage of implant surgical procedure and to attain some degree of compressive strength after the hydration. Additionally, the porosity is not overly reduced to maintain the ability for bone regeneration. The porosity of the samples was confirmed to be 40%–50% with the formation of the C3S matrices. Simultaneously, the maximum compressive strength was ensured at 14.9 MPa within 24 h of curing time. The radiopacity required for post‐procedural diagnosis was evaluated. The radiopacity of the samples with 50% and 60% C3S was 1.0 mm Al and 1.1 mm Al, respectively. When ZrO2 was added, the radiopacity was enhanced to 1.6 mm Al. Overall, the experimental results showed that the bone‐graft added C3S would be suitable for alveolar bone support and rigid matrix formation in implant surgery. [ABSTRACT FROM AUTHOR]

High‐performance compact capacitive energy storage is vital for many modern application fields, including grid power buffers, electric vehicles, and portable electronics. However, achieving exceptional volumetric performance in supercapacitors is still challenging and requires effective fabrication of electrode films with high ion‐accessible surface area and fast ion diffusion capability while simultaneously maintaining high density. Herein, a facile, efficient, and scalable method is developed for the fabrication of dense, porous, and disordered graphene through spark‐induced disorderly opening of graphene stacks combined with mechanical compression. The obtained disordered graphene achieves a high density of 1.18 g cm−3, sixfold enhanced ion conductivity compared to common laminar graphene, and an ultrahigh volumetric capacitance of 297 F cm−3 in ionic liquid electrolyte. The fabricated stack cells deliver a volumetric energy density of 94.2 Wh L−1 and a power density of 13.7 kW L−1, representing a critical breakthrough in capacitive energy storage. Moreover, the proposed disordered graphene electrodes are assembled into ionogel‐based all‐solid‐state pouch cells with high mechanical stability and multiple optional outputs, demonstrating great potential for flexible energy storage in practical applications. [ABSTRACT FROM AUTHOR]

Potassium metal batteries (PMBs) are promising for next‐generation energy storage. However, the high reactivity of the anode causes instability in the solid electrolyte interface (SEI), resulting in Volmer‐Weber (V‐W) type deposition. To achieve uniform Frank‐van der Merwe (F‐M) type deposition, high entropy alloy nanoparticles are designed (HEA NPs) with equimolar ratios of Mn, Fe, Co, Cu, and Ni to enhance the substrate‐K metal interface. HEA NPs enhance the K affinity of the N‐doped nanocarbon fiber substrate (N‐PCNF) and maximize ion and electron transport efficiency. The dendrite‐free horizontal growth of K metal confirmed through Operando X‐ray diffraction (XRD) and optical microscopy (OM). Consequently, the asymmetric cell exhibits ultra‐long cycling stability of 2350 hours at a high current density of 8 mA cm−2. The full cell composed of molten K diffusion into HEA NPs decorated N‐PCNF anode with perylene‐3,4,9,10‐tetracarboxylic dianhydride cathode (HEA‐N‐PCNF‐K||PTCDA) delivers an energy density of 331 W h kg−1 and remains stable over 2000 cycles. This study offers a promising pathway for innovative PMBs designs with broad application prospects. [ABSTRACT FROM AUTHOR]

Boosting the reaction stability without sacrificing the activity and cost is extremely important but full of challenges for the RuO2‐based oxygen evolution catalysts. Herein, porous and B‐site substituted Y2[Mn0.2Ru0.8]2O7 (p‐Y2[Mn0.2Ru0.8]2O7) pyrochlore toward oxygen evolution reaction is innovatively synthesized. The formed meso‐/macroporous structure can increase the specific surface area and corresponding active sites, meanwhile, Mn‐substitution can modulate the electronic structure, stabilize the morphology, and reduce the dosage of Ru species. Interestingly, the p‐Y2[Mn0.2Ru0.8]2O7 performs 50 h stable operation, significantly outperforming the commercial RuO2(CM) counterpart with less than 2 h life. Furthermore, the required overpotential to achieve 10 mA cm−2 is only 266 mV, accompanied with favorable reaction kinetics and catalyst utilization. [ABSTRACT FROM AUTHOR]

Oxygen evolution reaction (OER) is an important half-reaction of many actual processes, which has the slow kinetics of four-electron process. Interface engineering as an effective method can accelerate the slow kinetics of oxygen evolution reaction. In this paper, CoSe 2 –MoSe 2 porous nanosheet arrays with heterostructures were synthesized on carbon cloth by ion exchange and vapor phase selenization using Co-MOF as template. Due to the porous two-dimensional structure, the electron diffusion path is shortened and the self-supporting electrode has excellent conductivity. When catalyzing OER in 1 M KOH solution, the CoSe 2 –MoSe 2 delivers an overpotential of 278 mV at 10 mA cmm2, and Tafel slope of 61.2 mV dec−1, making catalytic activity a better result than commercial RuO 2. In addition, the decay of the catalytic activity is negligible after 24 h of continuous electrolysis. This work provides a method for the design of porous bimetallic selenide self-supporting oxygen evolution electrocatalysts. [Display omitted] • The CoSe 2 –MoSe 2 /CC was synthesized by ion exchange and gas-phase selenization. • The CoSe 2 –MoSe 2 /CC catalyst has porous nanosheet array morphology. • Porous CoSe 2 –MoSe 2 /CC exhibits excellent OER catalytic activity. [ABSTRACT FROM AUTHOR]

The semiconductor gas sensors with high sensitivity and low detection limit not only possesses significant importance in environmental monitoring, but also have great application in trace gas detection. In this study, we successfully synthesized Sn-doped ZIF-8 derived ZnO compound by combining solution-based and solid-phase sintering methods. The material's phase, morphology structure and functional groups were characterized using X-ray diffraction (XRD), scanning electron microscope (SEM) and Fourier-transform infrared spectroscopy (FT-IR). The ZnO: Sn sensor in this study exhibits excellent gas-sensitive performance, including ultra-high response (2 495), fast response/recovery time (52/9 s), and low detection limit (0.5 ppb) for 200 ppm NO2 at 180 °C. The excellent gas-sensitive performance of the ZnO: Sn sensor is mainly attributed to the porous structure of ZIF-8-derived ZnO, its large specific surface are- a,and the electron sensitization caused by Sn doping, which significantly improves the gassensitive performance of ZnO for NO2, and it is expected to be applied in the detection of low NO2 concentration with high sensitivity. [ABSTRACT FROM AUTHOR]

The development of absorber materials with strong light absorption properties and low-cost fabrication processes is highly significant for the application of photothermal conversion technology. In this work, a mixed powder consisting of NaCl, polypropylene (PP), and scale-like carbon flakes was ultrasonically pressed into sheets, and the NaCl was then removed by salt dissolution to obtain porous carbon polypropylene composite sheets (P-CPCS). This process is simple, green, and suitable for the low-cost, large-area fabrication of P-CPCS. P-CPCS has a well-distributed porous structure containing internal and external connected water paths. Under the dual effects of the carbon flakes and porous structure, P-CPCS shows excellent photothermal conversion performance in a broad wavelength range. P-CPCS-40 achieves a high temperature of 128 °C and a rapid heating rate of 12.4 °C/s under laser irradiation (808 nm wavelength, 1.2 W/cm2 power). When utilized for solar steam generation under 1 sun irradiation, P-CPCS-40 achieves 98.2% evaporation efficiency and a 1.81 kg m−2 h−1 evaporation rate. This performance means that P-CPCS-40 outperforms most other previously reported absorbers in terms of evaporation efficiency. The combination of carbon flakes, which provide a photothermal effect, and a porous polymer structure, which provides light-capturing properties, opens up a new strategy for desalination, sewage treatment, and other related fields. [ABSTRACT FROM AUTHOR]

A review of modern scientific literature on the electric double layer capacitors based on the recharging of the electric double layer is presented. The electric double layer capacitors are used in pulse technology devices, as electric energy storage devices, for starter firing, for the recuperating of the braking energy of internal combustion engines, for smoothing peak loads in electric networks, and in various portable devices. The electric double layer capacitors are subdivided into the power electric double layer capacitors and the energy ones. The power (pulse) electric double layer capacitors have a high specific power (up to hundreds of kW/kg), whereas the energy electric double layer capacitors have a high specific energy (~25 W h/kg and higher). Compared to batteries, the power electric double layer capacitors have a much higher power density and better cyclability—up to hundreds of thousands and millions of cycles. Publications on the electric double layer capacitors' self-discharge are reviewed. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Test & Measurement Technology is the property of Publishing Center of North University of China and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

As the frequency range of electronic devices gradually expands, exploring frequency insensitive electromagnetic wave adsorption (EWA) materials that can achieve effective absorption in all bands has aroused great interest. A series of Fe1 − xS@C composite materials with three-dimensional conductive networks were successfully prepared in this work. In the preparation process, poly (aryl ether sulfone) with branched carboxylic (PAES-C) was selected as the skeleton and Fe3+ ions were introduced via chemical adsorption. The main purpose of this work was to develop array porous composite materials with good EWA property. The work proposed a novel controllable method for preparing metal sulfides to explore the electromagnetic wave absorption. This routine was also developed to prepare other MxS@C composites (M = Fe, Cu, Mn). Compared to MnxS@C and CuxS@C composites, the RLmin value of Fe1 − xS@C-4 was − 40.6 dB at 13.52 GHz, and at a thickness of 1.5 mm the effective bandwidth reached 3.12 GHz. Furthermore, its effective absorption band covered Ku, X, and C radar bands at different thicknesses. Highlights: •MxS@C composites (M = Fe, Cu, Mn) are prepared for electromagnetic wave absorption. •A new research method for the synthesis of metal sulfides. •The RLmin of Fe1 − xS@C-4 is -40.6 dB, and the effective bandwidth of 3.12 GHz at 1.5 mm. •The absorption band of Fe1 − xS@C composites covered Ku, X, and C radar bands at different thicknesses. [ABSTRACT FROM AUTHOR]

[Objective] Gas--solid composite dielectrics are important electrical insulation materials widely used in civil and military high-tech fields, such as electrical/electronic engineering, aerospace, and strong electromagnetic pulse. However, composite insulation is prone to flashover under high electric fields, thus improving the surface flashover strength, which is a key issue in enhancing the overall performance of power equipment. The surface morphology of solid dielectrics has a significant impact on the flashover strength. However, existing surface microstructure tailoring methods are based on the etching approach, which can only construct surface holes or groove-like structures, and the morphology resolution is limited to the micrometer scale. In contrast to etching methods, which only change the surface morphology, this study constructs a three-dimensional foam-like porous structure to effectively enhance the surface flashover voltage. [Methods] Polydimethylsiloxane (PDMS) was selected as the matrix material to prepare bulk porous materials via the oil/water emulsion method. Deionized water was dispersed into PDMS by electrical stirring, and the PDMS and water droplets formed the oil/water emulsion. Afterward, PDMS was cross-linked and solidified by heating to form a porous structure with high mechanical strength. Three different mass ratios of deionized water to PDMS, namely 10%, 30%, and 50%, were considered in the experiments. A comprehensive experimental system was established to characterize the surface flashover characteristics of porous insulation materials under high voltage. The flashover strength in different gas atmospheres was tested in a closed gas discharge experimental chamber, and the initiation and development processes of surface discharge were analyzed through optoelectronic joint diagnosis. The isothermal surface potential decay method was employed to measure the trap energy distribution and explore the influence of porous structure on charge dissipation rate and trap distribution. A fluid simulation model for surface streamer propagation on porous solid dielectrics was built to analyze the influence of pores on the development process of surface discharge. [Results] Results showed that, with the increase in deionized water content, the pore size and porosity of porous PDMS gradually increased. Increasing the porosity and pore size can also effectively improve the hydrophobic performance. The porous structure effectively enhanced the surface flashover voltage, and the flashover strength increased with the porosity. The maximum increment in direct current flashover voltage was 53%. The surface potential scanning and streamer simulation results showed that the porous structure can effectively hinder the collision ionization process, thereby suppressing microdischarges. The measurement results of surface potential decay indicated that the mobility of charges in pores is higher than that on the surface of solid dielectrics. Therefore, the porous structure plays a role in promoting the dissipation of surface charges, which is enhanced with the increase in porosity. [Conclusions] The effects of hindering collision ionization and promoting surface charge dissipation by porous structures are beneficial for enhancing the surface flashover strength, and both effects are enhanced with the increase in porosity, resulting in an improvement in flashover strength with the increase in porosity. This experiment involves electrical engineering, materials, physics, and multiphysics field simulations, which can effectively improve students' comprehensive abilities in experimentation, simulation, and theoretical analysis. [ABSTRACT FROM AUTHOR]

Programmable matter refers to material that can be programmed to alter its physical properties, including its shape. Such matter can be built as a lattice of attached robotic modules, each seen as an autonomous agent with communication and motion capabilities. Self-reconfiguration consists in changing the initial arrangement of modules to form a desired goal shape, and is known to be a complex problem due to its algorithmic complexity and motion constraints. In this paper, we propose to use a max-flow algorithm as a centralized global planner to determine the concurrent paths to be traversed by modules through a porous structure composed of 3D Catoms meta-modules with the aim of increasing the parallelism of motions, and hence decreasing the self-reconfiguration time. We implement a traffic light system as a distributed asynchronous local planning algorithm to control the motions to avoid collisions. We evaluated our algorithm using VisibleSim simulator on different self-reconfiguration scenarios and compared the performance with an existing fully distributed synchronous self-reconfiguration algorithm for similar structures. The results show that the new method provides a significant gain in self-reconfiguration time and energy efficiency. [ABSTRACT FROM AUTHOR]

The paper describes the influence of the drum system construction of two modern carding machines on the porous structure of spunlace non-wovens composed of polyester and viscose. The non-woven fabric structure, including the number and size of the pores, determines the tensile strength of the composites obtained. The spunlace non-wovens were subjected to tensile strength tests in the machine, and cross-directions and microscopic observations of their structure were made. The results of the experiments were used to determine the relationship between the strength of the material and the porosity of its structure. This knowledge was used to prepare recommendations for the manufacturer of wet wipes in order to enable the selection of a carding machine for the mass production of final products with strength properties that meet market requirements and satisfy the end customer. [ABSTRACT FROM AUTHOR]

There is an increasing demand for durable metallic implants, particularly among elderly patients undergoing revision surgeries for degenerative bone diseases. Approximately 70–80% of the implants are made of metal. Despite their robustness, metallic implants exhibit a higher Young's modulus than bone, leading to a stress-shielding effect. Although porous structures in implants aim to mitigate this issue, their porosity compromises overall strength. The present study focuses on the design of porous gyroid Ti–6Al–4V specimens and their fabrication using laser powder bed fusion. Subsequently, hydroxyapatite (HAp) combined with polyamide binders was synthesized using the sol–gel method from precursors and infiltrated into porous specimens to enhance their bio-mechanical compatibility. The X-ray diffraction analysis confirmed the presence of both Ti–6Al–4V and HAp. The Tafel plots revealed that the corrosion rate of the porous specimen infiltrated with HAp was about 0.394 mm/year, which is very minimal considering the prolonged implant lifespan. Furthermore, the results from the compression testing revealed that the average Young's modulus and compressive strength of HAp-infiltrated specimens were found to be increased by 70% and 7.5% respectively when compared to the non-infiltrated porous gyroid Ti–6Al–4V samples. These findings confirm that the HAp not only enhances osseointegration and tissue growth but also enhances the compressive strength of the porous Ti–6Al–4V metallic implants. [ABSTRACT FROM AUTHOR]

With the increasing levels of CO2 emissions and the decreasing availability of energy resources, the electrocatalytic CO2 reduction reaction (CO2RR) offers a promising method for utilizing CO2 as a valuable resource using sustainable electrical energy. However, developing cost‐effective and highly efficient catalysts remains a significant challenge. Although zinc, an abundant element on Earth, has shown potential for converting CO2 into CO, its effectiveness as a catalyst for CO2 reduction is hindered by its low selectivity and stability. This study introduces a fast, efficient, and simple electrochemical deposition method for preparing porous zinc nanosheets (NS) using the hydrogen bubble template approach. The as‐prepared zinc NS catalyst demonstrates exceptional catalytic activity due to its highly porous structure and high specific surface area. At a voltage of −1 V versus RHE, it achieves a maximum CO Faradaic efficiency of 89.5 %. The performance of this system is characterized by a partial current density of around −6.17 mA cm−2 in an H‐cell configuration. Additionally, our catalyst exhibits remarkable durability over 10 h, highlighting its significant potential for real‐world utilization in CO2RR. [ABSTRACT FROM AUTHOR]

In recent years, passive radiative cooling has garnered considerable attention as a sustainable thermal regulation without relying on external energy sources, thus mitigating pollutants generation. However, an intrinsic limitation of these cooling systems lies in the reflective glare, often characterized by an ivory or silvery appearance. This drawback limits their practical application, especially where both functional efficiency and aesthetic appeal are pivotal. Herein, a biomimetic approach inspired by Saharan silver ants' thermoregulatory capabilities is adopted. These ants, equipped with distinctive triangular‐shaped hair, maintain body temperature lower than the ambient air. Leveraging insights from this natural model, a reusable silicon template is employed to fabricate a metasurface structural colored film with a triangular prism array structure using thermoplastic polyurethane (TPU) and the phase separation technique. The film demonstrates an average emissivity of 96% within the atmospheric window and an average solar reflectivity of 93%, leading to a maximum temperature reduction of 8.6 °C during daytime and 5.9 °C at night. Furthermore, the film displays stretchability and mechanical resilience, bolstered by the microscale prismatic structure enhancing superhydrophobicity. This work introduces a biomimetic strategy aimed at augmenting thermal emission while reconciling the challenge of achieving visual appealand high radiative cooling performance. [ABSTRACT FROM AUTHOR]

Tailoring the properties of cellulose aerogel beads was investigated in the present study by using weak organic acids as coagulants. Three different weak acids were specifically chosen, acetic acid, lactic acid and citric acid. For comparative studies, a strong acid, hydrochloric acid was examined. The production of aerogel beads by conventional dropping technique was controlled and optimized for weak acids. Aerogels were characterized by density analyses, scanning electron microscopy, nitrogen adsorption–desorption analysis, X‐ray powder diffractometry and IR spectroscopy. In common, all the aerogel beads showed interconnected nanofibrillar network, high specific surface area, high pore volume, high porosity and meso‐ and macroporous structure. In particular, when the weakest acid (acetic acid) was used as coagulant in the regeneration bath, the lowest shrinkage was observed. As a result, the cellulose aerogel beads produced from acetic acid showed the highest values of specific surface area (423 m2 g−1) and pore volume (3.6 cm3 g−1). The porous structure can be tuned by the choice of regeneration bath, which has either strong acid or a high concentration of weak acid. The aerogel beads were pure and showed cellulose II crystallinity. Hence this study paves an alternative path way to tailor the properties of cellulose aerogel beads. [ABSTRACT FROM AUTHOR]

A mathematical model was developed for the calculation of thermal processes occurring in hexagonally located cells in the form of connected channels with a filler. The proposed model was used to calculate the temperature fields and power of heat flows along a single homogeneous long thin rod of calcium carbonate perovskite embedded in the hexagonally arranged channels of anodic aluminum oxide. In addition, the equations for calculating the distribution of temperature and power of heat flows in the wall of the aluminum oxide channel in the perpendicular direction were derived. The resulting calculations can be used to develop advanced highly efficient solar power electronic devices. [ABSTRACT FROM AUTHOR]

This study aimed to analyze the feasibility of removing Alizarin red S (ARS) used as model pollutant from aqueous solutions using the preparative porous silica composites (PSCs) as adsorbents which were prepared via hydrothermal approach. The physicochemical properties of materials were characterized by means of Transmission electron microscope (TEM), Scanning electron microscope (SEM), Energy dispersive spectrometer (EDS), Brunauer-Emmett-Teller (BET) method, Barret-Joyner-Halenda (BJH) method, Fourier Transform Infrared Spectrometer (FTIR) and X-Ray Diffractometer (XRD). PSCs possessed the specific surface area were 731.6 m2/g, 420.9 m2/g, 294.6 m2/g, respectively. The presence of silica structures was confirmed by FTIR spectra. In order to confirm efficiency of composites as adsorbents and reveal adsorption mechanism, the impacts of pH, contact time, initial ARS concentration, temperature on adsorption were conducted. The adsorption experiment results showed that the adsorption efficiency of ARS onto PSC-3 was better than that of PSC-1 and PSC-2 at pH = 11. Furthermore, the adsorption kinetic models, isotherm models and thermodynamic model were analyzed for comprehensive adsorption process. The maximum adsorption capacity of PSC-3 for ARS was 43.1 mg/g. The pseudo-second-order kinetic model and Sips isotherm model were more suitable for experimental results. The adsorption process was endothermic according to the adsorption thermodynamic model. The free energy of adsorption required for ARS onto PSCs was less than 8 kJ/mol, indicating physical adsorption. What's more, PSC-3 possessed advantages of higher adsorption capacity and shorter equilibration time. Overall, these results made it potentially applicable as an effective adsorbent for ARS dye from effluent. [ABSTRACT FROM AUTHOR]

The Hot Isostatic Pressing (HIP) process is based on the combined action of high levels of pressure and temperature. In general, such a process is used for reducing or eliminating microporosities in the component, especially when it is produced by additive manufacturing (AM) or casting. In the present work HIP is used for compacting TI6Al4V-ELI powders by means of a pressurized Argon gas acting at high temperature on a sealed can under vacuum in which Argon is previously inflated; thus, a subsequent Solid-State Foaming (SSF) heat treatment allows to produce a Titanium foam without any melting by exploiting gas entrapment. Samples extracted from billets produced setting different HIP parameters (size of Titanium particles and pressures) have been investigated in this work by means of heat treatments in furnace for the SSF: the temperature was kept constant (1020 °C), but the duration was varied in the range 1 - 6 h; the samples were finally analysed by Light Microscopy. Finally, the Response Surface Method (RSM) was used to determine the conditions able to increase both the size and the percentage area of the pores in order to fully control both the involved processes (HIP and SSF). Experimental results revealed that the porosity determined by the SSF is strongly affected by HIP parameters and by the SSF duration: the highest dimension of Ti particles and the highest level of Argon pressure determined the largest values of porosity, in terms of both percentage and pore dimension. The investigated process for producing porous titanium structures can be properly and efficiently combined with manufacturing processes able to create highly customised parts, not only in terms of geometry but also in terms of porosity. [ABSTRACT FROM AUTHOR]

As an energy-free cooling technique, radiative cooling has garnered significant attention in the field of energy conservation. However, traditional radiative cooling films often possess static optical properties and their inherent opacity limits their applications in building such as windows. Therefore, there exists a requirement for passive radiative cooling films endowed with adjustable transmittance. Here we report the porous block copolymer films with self-adjustable optical transmittance and passive radiative cooling. In a result, the film exhibited a high solar reflectance (0.3–2.5 µm) of 96.9% and a high infrared emittance (8–13 µm) of 97.9%. Outdoor experiments demonstrated that the film surface temperature was 6.6 °C lower than ambient temperature, with a cooling power of 104.8 W·m−2. In addition, the film's transmittance can be regulated by altering the polarity of the postprocessing solvent, providing an effective approach for regulating indoor light intensity and thermal balance, thereby enhancing the applicability of radiative cooling. [ABSTRACT FROM AUTHOR]

Porous carbon materials, including activated carbon nanofibers (ACNFs), have wide applications in the fields of recycling, separation, storage, drug delivery, etc. due to their high surface area and high porosity. On the other hand, the combination of these materials with graphene structures may have a synergistic effect on the properties of the product for the target application. In the present research, polyacrylonitrile nanofibers containing different percentages of synthesized graphene oxide, functionalized by chlorosulfonic acid were produced by the electrospinning method. Then, carbonization and activation were carried out to produce a porous activated carbon nanofibrous web. The investigation proved that the average diameter of the functionalized graphene oxide (FGO) incorporated PAN nanofibers increases as the amount of the incorporated FGO is increased. FESEM micrographs showed that the FGO incorporated nanofibers disfigure to some extent after activation, whereas the neat PAN nanofibers keep their original fiber form. XRD analysis showed that after activation, the Dspacing in FGO-incorporated nanofibers decreases to some extent, but generally the effect of FGO on the microstructure of PAN nanofibers is not overwhelming. FTIR spectrum confirmed the presence of FGO in ACNFs. BET results showed that the specific surface area of the ACNF decreases with increasing amounts of the incorporated FGO. The maximum specific surface area recorded was 941.37 m2/g. This was lower than that of the neat ACNF (988.5 m2/g). Total pore volume showed the same trend. The presence of FGO in ACNFs leads to an increase in mesopores content and in other words, the share of micropores decreases. [ABSTRACT FROM AUTHOR]

Copyright of Science & Technology of Cereals, Oils & Foods is the property of Science & Technology of Cereals, Oils & Foods Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Biodegradable elastic poly(L‐lactide‐co‐ε‐caprolactone) (PLCL) copolymer (50:50, lactide:caprolactone molar ratio) was synthesized and porous PLCL micropowders was fabricated by a simple method involving rapid cooling of 0.1, 0.5, and 1% (wt/vol) PLCL/dioxane spray into liquid nitrogen. The physicochemical properties of the porous PLCL micropowders were examined by measuring their pore size, pore morphology, and microbead size using a scanning electron microscopy (SEM) and dye and temozolomide (TMZ)‐release testing under ultrasound. Human U‐87MG, glioblastoma (GBM) cell culture tests were performed to evaluate cell cytotoxicity by released drug from PLCL micropowders. In this study, the porous PLCL micropowders prepared from 1 wt%/vol% PLCL solutions showed a highly porous structure, satisfactory mechanical properties, and optimal drug release efficiency compared with those produced from 0.1 or 0.5 wt%/vol% solutions. The results of the accumulated release test with the results of the absorbance of the dye initially applied, it was confirmed that more than 80% of the added dye was trapped inside the micropowder, and clearly GBM cytotoxicity effect could be observed by the released TMZ. The drug release system using micropowders and ultrasound can be applied as a drug supply system for various diseases such as brain tumors with low drug permeability. [ABSTRACT FROM AUTHOR]

Dendrites, passivation, and other adverse reactions impede ZnO from being a high-density anode in alkaline zinc-nickel batteries. With heat treatment and precipitation methods, ZnO nanosheets were uniformly grown on the surface of nitrogen-doped porous carbon (NPC), the composites named ZnO@NPC. ZnO@NPC, a new composite as the anode material of zinc-nickel batteries, was inspected for excellent cycle performance during the charge and discharge process at a high rate (8 C), and the capacity retention with a discharge specific capacity of 570.6 mAh g−1 is 97.54% of the initial discharge capacity (585 mAh g−1) after 2000 cycles. The approach suggested in this paper lends credence to the idea that ZnO@NPC is a promising material for zinc-nickel batteries in the near future. [ABSTRACT FROM AUTHOR]

Developing lightweight, highly active surfaces with a high level of performance and great stability is crucial for ensuring the dependability of energy harvesting and conversion devices. Aerogel-based electrocatalysts are an efficient option for electrocatalytic hydrogen production because of their numerous benefits, such as their compatibility with interface engineering and their porous architecture. Herein, we report on the facile synthesis of a nanorod-like molybdenum sulfide–reduced graphene oxide (M-rG) aerogel as an electrocatalyst for the hydrogen evolution reaction (HER). The 3D architecture of the network-like structure of the M-rG hybrid aerogel was created via the hydrothermal technique, using a saturated NaCl solution-assisted process, where the MoS2 was homogeneously incorporated within the interconnected rGO aerogel. The optimized M-rG-300 aerogel electrocatalyst had a significantly decreased overpotential of 112 mV at 10 mA/cm2 for the HER in alkaline conditions. The M-rG-300 also showed a higher level of reliability. The remarkable efficiency of the HER involving the M-rG-300 is principally attributed to the excellent connectivity between the rGO and MoS2 in the aerogel structure. The efficient interconnection influenced the achievement of a larger electrochemically active surface area, increased electrical conductivity, and the exposure of more active sites for the HER. Furthermore, the creation of a synergistic effect in the M-rG-300 aerogel is the most probable mechanism to boost the electrocatalytic activity. [ABSTRACT FROM AUTHOR]

Triply periodic minimal surfaces (TPMSs) show potential as porous materials in different engineering applications. Amongst them, heat sink is the subject of this paper. The advantage of such a structure is the ability to design it based on the intended applications. In the present paper, an attempt is made to experiment with a better understanding of the performance of TPMSs in heat sink applications. The experiment was conducted for different flow rates, and two heat sink materials, aluminum and silver, were used. In addition, two fluids were used experimentally: The first was water, and the second was a mixture of water containing 0.6% aluminum nanoparticles and identified as a nanofluid. The applied heat flux was maintained constant at 30,800 W/m2. The results reveal experimentally and confirm numerically that the TPMS structure secures a uniform heat extraction in the system. The development of the boundary layer in the porous structure is reduced due to the current structure design. A higher Nusselt number is obtained when the nanofluid is used as the circulating fluid. The performance evaluation criteria in the presence of the nanofluid exceed 100. [ABSTRACT FROM AUTHOR]

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Food dehydration, the process of reducing moisture in food to improve shelf life, is one of the oldest food preservation methods used by the food processing industry. During dehydration, the porous structure within foods undergoes various alterations, significantly impacting both process efficiency and consumer acceptance. The types of pores, namely, open pores, characterized by connectivity to the external surface of the food, and closed pores, which lack external surface access, distinctly influence the dehydration and rehydration kinetics, stability of the dehydrated product, and textural properties of foods, such as hardness, strength, crispness, and chewiness. This study aims to comprehensively investigate the characteristics of open and closed pores and examine their distinct impacts on food attributes. It seeks to explore the mechanisms underlying pore formation and assess the effects of varied dehydration technologies on pore structure. It finally evaluates the applicable measurement methodologies and identifies the challenges and opportunities of measuring pores within the food industry. Furthermore, this study examined the utility of artificial intelligence in porosity modeling and discussed the potential for encapsulating functional compounds within pores. Overall, this comprehensive review provides valuable insights into the distinct characteristics and implications of open and closed pores on dehydrated food products. [ABSTRACT FROM AUTHOR]

Porous implants composed of periodically-repeating porous units have been applied in orthopedic surgeries to replace damaged bones. An important requirement for bone implants is to find a balance between biological and mechanical properties, that is, to ensure high pore connectivity and a certain strength. In this work, center-supported and perimeter-supported porous optimization models were established by a swarm intelligence optimization algorithm, and the corresponding titanium porous samples were fabricated by laser powder bed fusion (L-PBF). The effects of cell topology and porosity on the compressive behavior of L-PBF titanium porous structures were systematically investigated by a combination of compression simulation and experiments. Compression simulation shows that the deformation failure behavior of center-supported and perimeter-supported porous structures consists of three stages: elastic deformation, plastic deformation and compression collapse, showing the characteristics of elastic-plastic porous materials. According to the compression test results, the compressive strength of center-supported and perimeter-supported structure samples are 151–188 MPa and 178–196 MPa, respectively, and the compressive stability of the perimeter-supported structure is better than that of the center-supported structure. The porosity error of center-supported structure is 1.6%–2.9%, and the porosity error of perimeter-supported structure is 3.1%–4.5%. The compressive strength of the same type of structure decreases with the increase of the porosity of the porous structure. The simulation/experimental compressive strength errors of center-supported and perimeter-supported structures are less than 6% and 5.9%, respectively. The constructed quasi-static compression model has certain guiding significance for the study of the fracture of the titanium implants under external force.

Abstract Based on the advantages of triply periodic minimal surface (TPMS) porous structures, extensive research on NiTi shape memory alloy TPMS scaffolds has been conducted. However, the current reports about TPMS porous structures highly rely on the implicit equation, which limited the design flexibility. In this work, novel shell-based TPMS structures were designed and fabricated by laser powder bed fusion. The comparisons of manufacturability, mechanical properties, and shape recovery responses between traditional solid-based and novel shell-based TPMS structures were evaluated. Results indicated that the shell-based TPMS porous structures possessed larger Young’s moduli and higher compressive strengths. Specifically, Diamond shell structure possessed the highest Young’s moduli of 605.8±24.5 MPa, while Gyroid shell structure possessed the highest compressive strength of 43.90±3.32 MPa. In addition, because of the larger specific surface area, higher critical stress to induce martensite transformation, and lower austenite finish temperature, the Diamond shell porous structure exhibited much higher shape recovery performance (only 0.1% residual strain left at pre-strains of 6%) than other porous structures. These results substantially uncover the effects of structural topology on the mechanical properties and shape recovery responses of NiTi shape memory alloy scaffolds, and confirm the effectiveness of this novel structural design method. This research can provide guidance for the structural design application of NiTi porous scaffolds in bone implants.

In the process of grain storage, the use of low-temperature grain storage technology can effectively reduce grain losses during storage and ensure grain quality, which is of great significance for maintaining a stable grain supply. Radiative cooling materials, as a new energy-free cooling technology, achieve cooling by radiating heat in the form of electromagnetic waves into outer space. This approach can address issues associated with traditional cooling methods, such as high energy consumption and high chemical oxygen demand (COD) emissions, offering a green and environmentally friendly new approach to low-temperature grain storage. This paper explained the working principle of polymer-based radiative cooling materials and systematically introduced the composition and selection criteria of polymer-based radiative cooling systems. It also categorized and summarized polymer-based radiative cooling materials according to their structural characteristics. The existing problems with different structured radiative cooling materials, as well as future research directions, were also analyzed. This provides a certain research framework for applying radiative cooling materials to grain storage facilities to achieve low-temperature grain storage.

[Display omitted] • FeOOH/F-Ce composites exhibit excellent catalytic activity under visible light. • The two-dimensional porous structure facilitates the diffusion and transport of reactant molecules, enhancing the degradation efficiency. • The S-scheme heterojunction promotes visible light absorption and charge transfer, accelerating the Fe3+/Fe2+ cycle. The utilization of two-dimensional (2D) materials to construct heterogeneous catalysts provides opportunities for environmental remediation, while the incorporation of porous structures can further enhance catalytic performance. In this work, a porous 2D FeOOH/fluorine-cerium (F-Ce) nanosheet composite was designed and synthesized by a simple impregnation-precipitation method. The unique 2D porous structure of F-Ce promoted the high dispersion of FeOOH quantum dots (QDs) (∼1.4 nm) and their tight integration to form S-scheme heterojunctions. This structure offered a greater number of active sites, and significantly improved the capacity of light absorption and the separation and migration efficiency of photogenerated carriers, thus improving catalytic activity. This catalyst achieved a phenol removal rate of 98.1 % within 20 min during the photo-Fenton reaction, which significantly surpasses pure FeOOH (32.9 %) and F-Ce (21.7 %) alone. In particular, the optimized 14FeOOH/F-Ce catalyst achieved more than 95.0 % degradation efficiency within a remarkably short period of 5 min. Mott Schottky and in situ irradiated X-ray photoelectron spectroscopy (ISI-XPS) studies demonstrated that the S-scheme charge transfer mechanism of this heterojunction synergistically enhanced the catalytic activity of the Fenton-like reaction. This study provides valuable insights for designing efficient 2D porous heterojunction catalysts for visible-light-driven Fenton applications. [ABSTRACT FROM AUTHOR]

[Display omitted] A composite material with a high potential for absorbing electromagnetic waves (EMW) was obtained by selecting poly (vinylidene fluoride) (PVDF) as the matrix, MXene as the conductive filler, and cobalt ferrite (CoFe 2 O 4) as the magnetic filler. A layer-by-layer assembly strategy involved hot pressing and sequential blade coating, followed by vapor-induced phase separation, was used to implement the preparation of PVDF/MXene/CoFe 2 O 4 (PMC) composites. The process facilitates the formation of a well-organized multilayer porous framework, providing a gradient of positive conductivity, negative magnetism, and porosity within the composites. Incorporating distinct multilayer, porous, and gradient structures into a single composite led to exceptional impedance matching (Z), with an area percentage of up to 8.4 % in the optimal range of 0.8 to 1.2. Furthermore, the multiple interfaces formed by the various components, multilayer structure, and porous configuration significantly enhanced the EMW attenuation capability, with the attenuation constant reaching as high as 274. Consequently, the PMC composite demonstrated outstanding performance with a minimal reflection loss (RL min) of −56.5 dB, a specific RL min of 23.5 dB/mm, and the broadest effective absorption bandwidth of 3.2 GHz. The combination of the competitive EMW absorption capability, low density, flexibility, adequate tensile strength, and amphiphilic Janus surface may significantly broaden the application scenarios of PMC composites. [ABSTRACT FROM AUTHOR]