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Surface segregation method, as an in situ method for simultaneous modification of membrane external surfaces and inner pore surfaces, has been more commonly employed to fabricate antifouling membranes. In this study, dopamine (DA) with self‐polymerization and bio‐adhesion ability is chosen as a surface segregation agent to fabricate antifouling polyvinylidene fluoride (PVDF) membrane for oil‐in‐water emulsions separation through synergistically regulating phase inversion, self‐polymerization of DA, and surface segregation of poly‐dopamine (PDA). During the phase inversion process, DA contacts with an alkaline coagulation bath to trigger self‐polymerization of DA, then the surface segregation of PDA proceeds spontaneously. The addition and self‐polymerization of DA can regulate the phase inversion process to acquire membranes with high porosity, as a result, the water permeance is increased from 134 to 538 L m−2 h−1 bar−1 with the oil rejection higher than 99.8%. Because the hydrophilic PDA layer on membrane and pore surfaces leads to a robust hydration layer, the membrane exhibits super‐oleophobicity underwater and excellent antifouling properties with water recovery ratio of more than 99.4%. This study may open a new route to preparing antifouling membranes by using small molecules as surface segregation agents. [ABSTRACT FROM AUTHOR]

In order to realize the intelligent diagnosis of rolling bearing failure,a fault diagnosis model of vibration signal based on empirical mode decomposition（ EMD） and deep belief network（ DBN） is proposed.Firstly,the vibration signal is processed by empirical mode decomposition,and the statistical parameters of the effective intrinsic modal function（ IMF） component and its Hilbert envelope are obtained as the original feature set. Then,the extreme learning suite（ ELM） classifier feature selection method is proposed to remove the redundancy and interference characteristics of the original feature set and to select the fault state sensitive features. Finally,by using the depth learning advantages in high-dimensional and non-linear processing,the DBN-based fault feature adaptive analysis and fault state intelligent identification is completed. The results show that the ELM method can select the sensitive statistical characteristics of the fault,and the adaptive characteristic of the DBN method can effectively improve the accuracy of fault state recognition.

As a highly promising approach to solving the issues of energy and environment, membrane technology has gained increasing attention in various fields including water treatment, liquid separations, and gas separations, owing to its high energy efficiency and eco‐friendliness. Surface segregation, a phenomenon widely found in nature, exhibits irreplaceable advantages in membrane fabrication since it is an in situ method for synchronous modification of membrane and pore surfaces during the membrane forming process. Meanwhile, combined with the development of synthesis chemistry and nanomaterial, the group has developed surface segregation as a versatile membrane fabrication method using diverse surface segregation agents. In this review, the recent breakthroughs in surface segregation methods and their applications in membrane fabrication are first briefly introduced. Then, the surface segregation phenomena and the classification of surface segregation agents are discussed. As the major part of this review, the authors focus on surface segregation methods including free surface segregation, forced surface segregation, synergistic surface segregation, and reaction‐enhanced surface segregation. The strategies for regulating the physical and chemical microenvironments of membrane and pore surfaces through the surface segregation method are emphasized. The representative applications of surface segregation membranes are presented. Finally, the current challenges and future perspectives are highlighted. [ABSTRACT FROM AUTHOR]

Sepsis-associated acute liver injury caused by spillovers of bacteria and endotoxins (lipopolysaccharide, LPS) into the liver remains a public health issue due to the lack of specific therapeutic approaches. Previous studies showed that the recombinant protein HscB (rCsHscB) of Clonorchis sinensis, a carcinogenic liver fluke, had an anti-inflammatory effect and could alleviate inflammatory diseases such as enteritis; however, whether it can prevent sepsis-associated acute liver injury induced by LPS is still unknown. In our current study, the therapeutic effects and the potential mechanisms of rCsHscB on LPS-induced acute liver injury were investigated both in vivo and in vitro. The data showed that rCsHscB prevented LPS-induced liver damage, as demonstrated by histopathological observation and hepatic damage markers (the activities of serum ALT and AST) in a murine model of sepsis-associated acute liver injury. rCsHscB also significantly reversed the high levels of serum IL-6 and MCP-1 induced by LPS. In addition, rCsHscB attenuated the production of LPS-induced proinflammatory cytokines, including IL-6 and TNF-α, in a macrophage cell line-RAW264.7, through possible mediation by the MAPK signaling pathway in vitro. In conclusion, the present study demonstrates that rCsHscB derived from a fluke C. sinensis protects against sepsis-associated acute liver injury induced by LPS, which may be attributed to the inhibition of the MAPK signaling pathway. Our present study provides a potential therapeutic strategy for sepsis-associated acute liver injury. [ABSTRACT FROM AUTHOR]

Robust and highly conductive proton exchange membranes are urgently required in fuel cells. Inspired by the underwater adhesion of sandcastle worms, herein, ultra-robust and highly conductive polymer carbon dot membranes (PCDMs) were fabricated via electrostatic complexation between zero-dimensional acidic group functionalized polymer carbon dots (PCDs) and sulfonated polyether ether ketone (SPEEK) in water solution. PCDs with different acid groups were designed to modulate the electrostatic complexation. The superior interface compatibility endows PCDMs with the highest PCD content of 50 wt%, meanwhile, phosphate functionalized PCDs endow the PCDMs with abundant proton transport sites and a low energy barrier proton transport pathway. As a result, the corresponding PCDMs exhibited a high proton conductivity of 264 mS cm−1 under 100% RH at 80 °C. Meanwhile, the PCDMs exhibited a high stress of 56 MPa and dimensional stability under 100% RH at 80 °C. [ABSTRACT FROM AUTHOR]

In vehicular networks, caching content in fog nodes is a widely accepted and favorable way to quickly respond to massive vehicle requests, reduce content retrieval delay and improve service quality. However, to implement such caching mode, it is critical to ensure efficient security and privacy protection when vehicles access the cached content in fog nodes. In this paper, aiming at the security issue, a novel lightweight cryptography-based access control scheme for software defined vehicular networks (SDVN) is proposed, by using TESLA broadcast authentication protocol and Pederson commitment. The scheme realizes direct and efficient authentication between vehicles and fog nodes while limiting only legitimate vehicles can get request responses, and avoids limitations or deficiencies in existing access control schemes. Moreover, considering the limited cache space of the fog node, by utilizing the flexibility of the SDN paradigm, a cooperative cache update mechanism is provided. The security verification with ProVerif and detailed security analyses prove that the scheme can meet the security requirements in SDVN. And compared with the related works, our scheme achieves better performance in terms of computation and communication costs. [ABSTRACT FROM AUTHOR]

Proton exchange membranes (PEMs) integrating high proton conductivity and exceptional mechanical properties are desirable for numerous energy-related fields. Here, a zero-dimensional (0D) graphene quantum dot (GQD) functionalized with phosphoric acid groups was intercalated into two-dimensional (2D) sulfonated COF nanosheets to fabricate robust PEMs. The optimal GQD-intercalated COF membrane exhibits superior proton conductivity at both high and low relative humidities (0.923 and 0.096 S cm−1 at 90 °C, 100% and 40% relative humidity, respectively) and a high tensile strength of ∼129 MPa, greatly surpassing the state-of-the-art PEMs. These unprecedented properties mainly stem from the ultrahigh density and regular arrangement of proton carriers in the long-range ordered proton conductive channels as well as multiple interactions including π–π interactions and electrostatic interactions between the functionalized GQDs and sulfonated COF nanosheets. This 0D/2D co-assembled strategy offers an efficient and facile way for the development of robust and high-performance membranes appealing to various applications. [ABSTRACT FROM AUTHOR]

Covalent organic framework (COF) membranes hold potential for widespread applicability, but scalable fabrication is challenging. Here, we demonstrate the disorder‐to‐order transformation from amorphous polymeric membrane to crystalline COF membrane via monomer exchange. Solution processing is used to prepare amorphous membrane and the replacing monomer is selected based on the chemical and thermodynamical stability of the final framework. Reversible imine bonds allow the extraneous monomers to replace the pristine monomers within amorphous membrane, driving the transformation from disordered network to ordered framework. Incorporation of intramolecular hydrogen bonds enables the crystalline COF to imprint the amorphous membrane morphology. The COF membranes harvest proton conductivity up to 0.53 S cm−1 at 80 °C. Our strategy bridges amorphous polymeric and crystalline COF membranes for large‐scale fabrication of COF membranes and affords guidance on materials processing. [ABSTRACT FROM AUTHOR]

Fabricating covalent organic frameworks (COFs) membranes with tight structure, which can fully utilize well‐defined framework structure and thus achieve superior conduction performance, remains a grand challenge. Herein, through molecular precursor engineering of COFs, we reported the fabrication of tight COFs membrane with the ever‐reported highest hydroxide ion conductivity over 200 mS cm−1 at 80 °C, 100 % RH. Six quaternary ammonium‐functionalized COFs were synthesized by assembling functional hydrazides and different aldehyde precursors. In an organic‐aqueous reaction system, the impact of the aldehyde precursors with different size, electrophilicity and hydrophilicity on the reaction‐diffusion process for fabricating COFs membranes was elucidated. Particularly, more hydrophilic aldehydes were prone to push the reaction zone from the interface region to the aqueous phase of the reaction system, the tight membranes were thus fabricated via phase‐transfer polymerization process, conferring around 4–8 times the anion conductivity over the loose membranes via interfacial polymerization process. [ABSTRACT FROM AUTHOR]

Lamellar membranes with two-dimensional nanofluidic channels hold great promise in harvesting osmotic energy from salinity gradients. However, the power density is often limited by the high transmembrane resistance primarily caused by the tortuous interlayer ion diffusion pathway. Here, we demonstrate the great potential of lamellar porous vermiculite membranes (PVMs) as efficient nanofluidic osmotic energy generators. The artificial in-plane nanopores on vermiculite nanosheets dramatically decrease the tortuosity and offer additional vertical ion pathways, substantially elevating the transmembrane ion flux. Meanwhile, the confined interlayer spacing serves as the selective barrier, contributing to a high ion selectivity. When operating under a 1000-fold salinity gradient, the PVMs achieve a 16-fold increase in output power density compared with nonporous vermiculite membranes, with a maximum value of 10.9 W m−2 that outperforms those of most of the state-of-the-art 2D lamellar membranes. [ABSTRACT FROM AUTHOR]

Multilamellar ZSM-5 nanosheets have been prepared using silicalite-1 as a seed in the presence of commercially available dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride (TPOAC). Characterization results show that these ZSM-5 nanosheets stack disorderly forming lamellar aggregates. Besides, there exists abundant interlayer space in these aggregates which penetrates the whole crystals and results in the formation of inter-connected mesopores. The methanol to gasoline (MTG) reaction has been applied as a probe reaction to evaluate the catalytic performance of ZSM-5 nanosheets. Compared with a ZSM-5 zeolite prepared without TPOAC, the multilamellar ZSM-5 nanosheets displayed an extraordinarily long MTG catalytic lifetime with a similar yield of gasoline range hydrocarbons, which could be reasonably attributed to the special morphology of the nanosheets. To reveal the crystallization mechanism of ZSM-5 nanosheets, the crystallization was stopped at different times first at 120 °C and then at 170 °C. The characterization results show that there exists a unique process of MCM-41-like mesophase formation and then transformation to crystalline MFI phases during a certain period of crystallization. [ABSTRACT FROM AUTHOR]

In order to enhance the performance of bearing fault diagnosis and classification, features extraction and features dimensionality reduction have become more important. The original statistical feature set was calculated from single branch reconstruction vibration signals obtained by using maximal overlap discrete wavelet packet transform (MODWPT). In order to reduce redundancy information of original statistical feature set, features selection by adjusted rand index and sum of within-class mean deviations (FSASD) was proposed to select fault sensitive features. Furthermore, a modified features dimensionality reduction method, supervised neighborhood preserving embedding with label information (SNPEL), was proposed to realize low-dimensional representations for high-dimensional feature space. Finally, vibration signals collected from two experimental test rigs were employed to evaluate the performance of the proposed procedure. The results show that the effectiveness, adaptability, and superiority of the proposed procedure can serve as an intelligent bearing fault diagnosis system. [ABSTRACT FROM AUTHOR]