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The forming interface is the weak link of thermoplastic composite complex structures. To explore the effect of polymer crosslinking on the failure behavior of thermoplastic composite remelting interface using "Preforming + Remelting bonding" process, the all‐atom models of different types of interfaces were established, and a molecular dynamics (MD) simulation was conducted on the uniaxial tensile failure process of the remelting interface. The failure behavior of the remelting interface with different preforming processes was tested to verify the correctness of MD simulation, and the influencing mechanism of polymer crosslinking reactions in the preforming stage to the remelting interface properties was clarified. The results showed that the yield stress of the uncrosslinked interface reaches 283.2 MPa and 16.0% and 50.6% higher than that of the unilateral and bilateral crosslinked interfaces respectively. The polymer crosslinking reaction during the preforming stage will reduce the interlaminar bonding performance. The interlaminar shear strength (ILSS) of the uncrosslinked interface is 87.46 MPa and 7.21% and 27.36% higher than that of the unilateral and bilateral crosslinked interface respectively, and only 3.95% lower than that of the non‐remelting sample formed by standard process. This research provides a new approach for predicting and analyzing the effect of polymer crosslinking on remelting interface properties of thermoplastic composite using "Preforming + Remelting bonding" process. Highlights: The failure behavior of different thermoplastic composite remelting interfaces was studied.MD simulation was conducted on the uniaxial tensile failure process of the remelting interface.The influencing mechanism of polymer crosslinking reactions in the preforming stage to the remelting interface properties was clarified.It is effective to explore the failure mechanism of thermoplastic remelting interface by MD simulation. [ABSTRACT FROM AUTHOR]

The vibration pretreatment–microwave curing process can achieve high-quality molding under low-pressure conditions and is widely used in the curing of resin-based composites. This study investigated the effects of the vibration pretreatment process parameters on the void content and the fiber weight fraction of T700/TRE231; specifically, their influence on the interlaminar shear strength and impact strength of the composite. Initially, an orthogonal experimental design was employed with interlaminar shear strength as the optimization target, where vibration acceleration was determined as the primary factor and dwell time as the secondary factor. Concurrently, thermogravimetric analysis (TGA) was performed based on process parameters that corresponded to the extremum of interlaminar shear strength, revealing a 2.17% difference in fiber weight fraction among specimens with varying parameters, indicating a minimal effect of fiber weight fraction on mechanical properties. Optical digital microscope (ODM) analysis identified interlaminar large-size voids in specimens treated with vibration energy of 5 g and 15 g, while specimens subjected to a vibration energy of 10 g exhibited numerous small-sized voids within layers, suggesting that vibration acceleration influences void escape pathways. Finally, impact testing revealed the effect of the vibration pretreatment process parameters on the impact strength, implying a positive correlation between interlaminar shear strength and impact strength. [ABSTRACT FROM AUTHOR]

The primary challenge during the secondary bonding process of full-height honeycomb sandwich structures is the aramid honeycomb core's height shrinkage. This paper systematically investigated the height evolution behavior of the honeycomb core by using a creep testing machine. The results showed that the out-of-plane compression deformation curve of aramid honeycomb cores is mainly divided into three stages: the dehumidification stage, the pressurization stage and the creep stage. Under conditions of high temperature and pressure, height shrinkage was attributed to the dehydration caused by moisture infiltration, and the compression creep resulted from the slippage of polymer molecular chains. Dehydration shrinkage is stable, whereas compression creep reflects typical viscoelastic polymer characteristics. By employing the viscoelastic Burgers mechanical model and applying the nonlinear surface fitting method, the total height shrinkage deformation behavior of the aramid honeycomb core during the curing process can be accurately predicted by summing the above three stages. This research contributes valuable insights for the manufacturing process of honeycomb sandwich structures. [ABSTRACT FROM AUTHOR]

Highlights This work focused on the leakage of the composite pressure vessel with a structure consisting of an aluminum alloy inner liner, a composite winding layer, and an aluminum covering. Through applying the finite element simulation approach and leakage rate test, it was found that the average strain of the winding layer in the lap region at the pressure of 46 MPa is 0.0078. Additionally, the leakage rate of the covering adhesive joint was investigated by considering the deformation, revealing that the leakage rate increases with increasing test pressure. The leakage rate at the lap region with a length of 18 mm is 2.05 × 10−7 Pa·m3/s at 0.0078 strain decreasing by 1.46 and 2.31 times compared to those under 12 and 7 mm lengths, respectively. The leakage rate exhibits a strict inverse correlation with the length of the leakage path under a pressure of 0 MPa. Additionally, when the deformation remains below the critical strain threshold (approximately 0.6%), the relationship between pressure and leakage rate shows a linear positive correlation. When the deformation of the component exceeds the critical strain threshold, the leakage rate of the component is significantly affected by its deformation and an increase in overall deformation results in a greater increase in leakage rate. The relationship between the two exhibits a non‐linear trend. This work provides strong technical support for the leakage assessment of composite pressure vessels. Deformation of the pressure vessel was analyzed through theoretical and simulation approaches. Establishing the relationship between deformation and pressure in metal–metal lap structures. Leakage analysis for different metal–metal lap lengths and deformation conditions. [ABSTRACT FROM AUTHOR]

The well-known limitations of spray cooling on high-temperature solids at the Leidenfrost temperature point have been significantly improved by a composite structure of steel micropillar arrays and insulating thin films. However, the physical mechanism of a single droplet impact on the walls of high-temperature composite structures in spray cooling remains elusive. We have experimentally studied and quantified the kinematic and thermal transfer characteristics of a single droplet impacting high-temperature micropillar arrays with fiber membrane composite structures. In particular, micropillar arrays of ceramic materials of different shapes (rectangular and cylindrical) used in this study were made using the more flexible PμSL technique, for which precision reaches the micron level. The results show that the presence and different layouts (embedded or placed on top) of the fiber layer significantly affect the spreading coefficient and thermal transfer efficiency of the droplets after impact. In terms of kinematic characteristics, unrelated to the structure of micropillar arrays, compared to structures without film, the maximum spreading coefficient of droplets significantly increased by more than 40% (43% for rectangular, 46% for cylindrical) when the fiber film was placed on top, and increased by more than 20% (20% for rectangular, 33% for cylindrical) when the fiber film was embedded. In terms of thermal transfer characteristics, at a temperature of 200 °C, the presence of the fiber layer changed the wettability of the surface of the micropillar structure, leading to a certain extension of the total evaporation time of the droplets compared to the surface of the micropillar structure without film. [ABSTRACT FROM AUTHOR]

All‐solid‐state lithium batteries (ASSLBs) based on sulfide solid electrolytes (SEs) are one of the most promising strategies for next‐generation energy storage systems and electronic devices. However, the poor chemical/electrochemical stability of sulfide SEs with oxide cathode materials and high interfacial impedance, particularly due to physical contact failure, are the major limiting factors to the development of sulfide SEs in ASSLBs. Herein, the composite cathode of MOF‐derived Fe7S8@C and Li6PS5Br fabricated by an infiltration method (IN–Fe7S8) with dissoluble sulfide electrolyte (dissoluble SE) is reported. Dissoluble SE can easily infiltrate the porous sheet‐type Fe7S8@C cathode to homogeneously contact with Fe7S8 nanoparticles that are embedded in the surrounding carbon matrixes and form a fast ionic transport network. Benefiting from applying dissoluble SE and Fe7S8@C, the IN‐Fe7S8‐based cells displayed a reversible capacity of 510 mAh g−1 after 180 cycles at 0.045 mA cm−2 at 30 °C. This work demonstrates a novel and practical method for the development of high‐performance all‐sulfide‐based solid state batteries. [ABSTRACT FROM AUTHOR]

The deployment of lithium metal anode in solid‐state batteries with polymer electrolytes has been recognized as a promising approach to achieving high‐energy‐density technologies. However, the practical application of the polymer electrolytes is currently constrained by various challenges, including low ionic conductivity, inadequate electrochemical window, and poor interface stability. To address these issues, a novel eutectic‐based polymer electrolyte consisting of succinonitrile (SN) and poly (ethylene glycol) methyl ether acrylate (PEGMEA) is developed. The research results demonstrate that the interactions between SN and PEGMEA promote the dissociation of the lithium difluoro(oxalato) borate (LiDFOB) salt and increase the concentration of free Li+. The well‐designed eutectic‐based PAN1.2‐SPE (PEGMEA: SN=1: 1.2 mass ratio) exhibits high ionic conductivity of 1.30 mS cm−1 at 30 °C and superior interface stability with Li anode. The Li/Li symmetric cell based on PAN1.2‐SPE enables long‐term plating/stripping at 0.3 and 0.5 mA cm−2, and the Li/LiFePO4 cell achieves superior long‐term cycling stability (capacity retention of 80.3 % after 1500 cycles). Moreover, Li/LiFePO4 and Li/LiNi0.6Co0.2Mn0.2O2 pouch cells employing PAN1.2‐SPE demonstrate excellent cycling and safety characteristics. This study presents a new pathway for designing high‐performance polymer electrolytes and promotes the practical application of high‐stable lithium metal batteries. [ABSTRACT FROM AUTHOR]

Harmful algae blooms (HABs) can have significant adverse effects on coastal ecosystems and aquaculture resiliency. We collected samples from March to August at eight different stations in Haizhou Bay (China), a region with a high frequency of HABs, and used Illumina Novaseq high-throughput sequencing and multivariate statistical analysis to characterize the bacterial communities and their relationships with different environmental factors. We identified 27 phyla, 49 classes, 158 orders, 294 families, and 522 genera. Gammaproteobacteria, Alphaproteobacteria, Bacteroidia, Acidimicrobiia, Bacilli, Actinobacteria, Cyanobacteria, Clostridia, and Acidobacteria were the most abundant classes, and Acidobacteria, Bacteroidetes, Firmicutes, Actinobacteria, Chloroflexi, Proteobacteria, and Cyanobacteria were the keystone phyla. Based on the Mantel test and redundancy analysis, temperature was the main environmental factor affecting the structure of the bacterial communities, followed by silicate, dissolved organic phosphorus (DOP), and dissolved oxygen (DO). Among the genera with high OTU abundance, Nautella was co-related positively with DO and negatively with salinity; Planktomarina was co-related positively with salinity and negatively with nitrate and nitrite. Certain families (Flavobacteriaceae, Rhodobacteraceae, and Clade_I (SAR11 clade)) and genera (Methylophaga, Alteromonas, Oleiphilus, Marinobacter, Bacillus, Nautella, and Vibrio) had associations with phytoplankton species that were responsible for HABs. This research provides new insights into the characteristics of the bacterial communities that occur in coastal areas that have HABs and provides detailed descriptions of the spatial and temporal changes in the structure of these communities. [ABSTRACT FROM AUTHOR]

Poly(vinylidene fluoride) (PVDF)-based composite solid electrolytes (CSEs) are attracting widespread attention due to their superior electrochemical and mechanical properties. However, the PVDF has a strong polar group -CF2-, which easily continuously reacts with lithium metal, resulting in the instability of the solid electrolyte interface (SEI), which intensifies the formation of lithium dendrites. Herein, Tetrafluoro-1,4-benzoquinone (TFBQ) was selected as an additive in trace amounts to the PVDF/Li-based electrolytes. TFBQ uniformly formed lithophilic quinone lithium salt (Li2TFBQ) in the SEI. Li2TFBQ has high lithium-ion affinity and low potential barrier and can be used as the dominant agent to guide uniform lithium deposition. The results showed that PVDF/Li-TFBQ 0.05 with a mass ratio of PVDF to TFBQ of 1:0.05 had the highest ionic conductivity of 2.39 × 10−4 S cm−1, and the electrochemical stability window reached 5.0 V. Moreover, PVDF/Li-TFBQ CSE demonstrated superior lithium dendrite suppression, which was confirmed by long-term lithium stripping/sedimentation tests over 2000 and 650 h at a current of 0.1 and 0.2 mA cm−2, respectively. The assembled solid-state LiNi0.6Co0.2Mn0.2O2||Li cell showed an excellent performance rate and cycle stability at 30 °C. This study greatly promotes the practical research of solid-state electrolytes. [ABSTRACT FROM AUTHOR]

All‐solid‐state batteries (ASSBs) based on inorganic solid electrolytes (SEs) are one of the most promising strategies for next‐generation energy storage systems and electronic devices due to the higher energy density and intrinsic safety. However, the poor solid‐solid contact and restricted chemical/electrochemical stability of inorganic SEs both in cathode and anode SE interfaces cause contact failure and the degeneration of SEs during prolonged charge‐discharge processes. As a result, the increasing interface resistance significantly affects the coulombic efficiency and cycling performance of ASSBs. Herein, we present a fundamental understanding of physical contact and chemical/electrochemical features of ASSB interfaces based on mainstream inorganic SEs and summarize the recent work on interface modification. SE doping, optimizing morphology, introducing interlayer/coating layer, and utilizing compatible electrode materials are the key methods to prevent side reactions, which are discussed separately in cathode/anode‐SE interface. We also highlight the constant extra stack pressure applied during ASSB cycling, which is important to the electrochemical performance. Finally, our perspectives on interface modification for practical high‐performance ASSBs are put forward. [ABSTRACT FROM AUTHOR]

Vibration pretreatment microwave curing is a high-quality and efficient composite out-of-autoclave molding process. Focusing on interlaminar shear strength, the effects of pretreatment temperature, pretreatment time and vibration acceleration on the molding performance of composite components were analyzed sequentially using the orthogonal test design method; a scanning electron microscope (SEM) and optical digital microscope (ODM) were used to analyze the void content and fiber-resin bonding state of the specimens under different curing and molding processes. The results show that the influence order of the different vibration process parameters on the molding quality of the components was: vibration acceleration > pretreatment temperature > pretreatment time. Within the parameters analyzed in this study, the optimal vibration pretreatment process parameters were: pretreatment temperature of 90 °C, pretreatment time of 30 min, and vibration acceleration of 10 g. Using these parameters, the interlaminar shear strength of the component was 82.12 MPa and the void content was 0.37%. Compared with the microwave curing process, the void content decreased by 71.8%, and the interlaminar shear strength increased by 31.6%. The microscopic morphology and mechanical properties basically reached the same level as the standard autoclave process, which achieved a high-quality out-of-autoclave curing and molding manufacturing of aerospace composite components. [ABSTRACT FROM AUTHOR]

As a new type of energy-containing material, Ammonium dinitramide based liquid propellant has the advantages of being green, having low toxicity, good stability, and high safety performance. Traditional catalytic combustion methods require preheating of the catalytic bed and deactivation of the catalytic particles at high temperatures, while microwave ignition methods can effectively solve these problems. To study the combustion characteristics of ADN-based liquid propellants during microwave ignition, the influence of microwave power and gas flow rates on the combustion process are analyzed using experimental methods. A high-speed camera was used to observe the enhanced effects of microwave power and gas flow on plasma and flame. Combined with temperature measurement, the combustion process of ADN-based liquid propellants under the action of plasma was analyzed. The combustion process in the presence of microwaves was observed by comparing parameters such as flame length, flame temperature, and radical intensity. Those results show that, with the increase in microwave power, the luminous burning area of the flame grows significantly. The microwave power is increased by 250 W each, and the flame jet length is increased by nearly 20%. The increase in microwave power also leads to an increase in propellant combustion temperature, however, this increase gradually slows down. At a gas flow rate of 20 L/min, the ADN-based liquid propellant showed the best combustion performance with a maximum jet length of 14.51 cm and an average jet length increase of approximately 85.9% compared to 14 L/min. Too much gas flow rate will hinder the development of the jet, while the high-velocity airflow will have a cooling effect on the flame temperature. The results provide a basis for the specific parameter design of microwave ignition and promote the application of ADN-based liquid propellants in the aerospace field. [ABSTRACT FROM AUTHOR]

Band division multiplexing technology is a promising medium-term transitional solution to deal with the traffic flood, by leveraging the existing optical fiber transmission infrastructure. Additionally, the deployment of multi-band optical networks requires updating and upgrading key components, such as multi-band amplifiers and multi-band optical cross-connects. From cost view, it would be a promising way for operators to expand transmission capacity on some of the links with high priority, which are used heavily. Therefore, the application scenario of this paper is positioned in the C-C+L hybrid optical networks. In this scenario, the introduction of the L-band brings additional inter-band stimulated Raman scattering (ISRS) which is a non-negligible nonlinear effect, leading new constraint for service provisioning. This paper proposes an ISRS-aware routing, band, modulation, and spectrum assignment (RBMSA) scheme, considering the impact of ISRS generated by new requests on existing requests. By implementing the SNR re-verification, not only the transmission quality of the current request can be realized, but also the service quality of the existing requests will not be seriously degraded to be unacceptable. A two-dimensional model of request bandwidth and duration is established for band selection. Priority is provided for arranging the requests in the L-band when it is available. For each single request, when the least number of slots required by adopting different modulation formats is the same, lower-order modulation is preferred to improve its SNR tolerance of this request under the ISRS impact. Simulation results indicate that the proposed scheme can effectively decrease the blocking probability, and improve the channel SNR for the successfully established requests. [ABSTRACT FROM AUTHOR]

Secondary batteries have been widespread in the daily life causing an ever-growing demand for long-cycle lifespan and high-energy alkali-ion batteries. As an essential constituent part, electrode materials with superior electrochemical properties play a vital role in the battery systems. Here, an outstanding electrode of yolk-shell ZnS@C nanorods is developed, introducing considerable void space via a self-sacrificial template method. Such carbon encapsulated nanorods moderate integral electronic conductivity, thus ensuring rapid alkali-ions/electrons transporting. Furthermore, the porous structure of these nanorods endows enough void space to mitigate volume stress caused by the insertion/extraction of alkali-ions. Due to the unique structure, these yolk-shell ZnS@C nanorods achieve superior rate performance and cycling performance (740 mAh g-1 at 1.0 A g-1 after 540 cycles) for lithium-ion batteries. As a potassium-ion batteries anode, they achieve an ultra-long lifespan delivering 211.1 mAh g-1 at 1.0 A g-1 after 5700 cycles. The kinetic analysis reveals that these ZnS@C nanorods with considerable pseudocapacitive contribution benefit the fast lithiation/delithiation. Detailed transmission electron microscopy (TEM) and X-ray diffraction (XRD) analyses indicate that such yolk-shell ZnS@C anode is a typical reversible conversion reaction mechanism accomplished by alloying processes. This rational design strategy opens a window for the development of superior energy storage materials. [ABSTRACT FROM AUTHOR]

Solid‐state lithium metal batteries (SLMBs) are attracting enormous attention due to their enhanced safety and high theoretical energy density. However, the alkali lithium with high reducibility can react with the solid‐state electrolytes resulting in the inferior cycle lifespan. Herein, inspired by the idea of interface design, the 1‐butyl‐1‐methylpyrrolidinium bis(trifluoromethanesulfonyl) imide as an initiator to generate an artificial protective layer in polymer electrolyte is selected. Time‐of‐flight secondary ion mass spectrometry and X‐ray photoelectron spectroscopy reveal the stable solid electrolyte interface (SEI) is in situ formed between the electrolyte/Li interface. Scanning electron microscopy (SEM) images demonstrate that the constructed SEI can promote homogeneous Li deposition. As a result, the Li/Li symmetrical cells enable stable cycle ultralong‐term for over 4500 h. Moreover, the as‐prepared LiFePO4/Li SLMBs exhibit an impressive ultra‐long cycle lifespan over 1300 cycles at 1 C, as well as 1600 cycles at 0.5 C with a capacity retention ratio over 80%. This work offers an effective strategy for the construction of the stable electrolyte/Li interface, paving the way for the rapid development of long lifespan SLMBs. [ABSTRACT FROM AUTHOR]