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Highlights: Detailed summary of current trends in the advancement of flexible EMI shielding materials. The theoretical shielding mechanisms and the latest concept of "green shielding" index (gs) are outlined. Functional applications of flexible EMI shielding materials are introduced from thermal conductivity, hydrophobicity to transparency, sensing even multiple functions. Exclusive insights in challenges and future design strategies opportunities for flexible EMI shielding materials are provided. With rapid development of 5G communication technologies, electromagnetic interference (EMI) shielding for electronic devices has become an urgent demand in recent years, where the development of corresponding EMI shielding materials against detrimental electromagnetic radiation plays an essential role. Meanwhile, the EMI shielding materials with high flexibility and functional integrity are highly demanded for emerging shielding applications. Hitherto, a variety of flexible EMI shielding materials with lightweight and multifunctionalities have been developed. In this review, we not only introduce the recent development of flexible EMI shielding materials, but also elaborate the EMI shielding mechanisms and the index for "green EMI shielding" performance. In addition, the construction strategies for sophisticated multifunctionalities of flexible shielding materials are summarized. Finally, we propose several possible research directions for flexible EMI shielding materials in near future, which could be inspirational to the fast-growing next-generation flexible electronic devices with reliable and multipurpose protections as offered by EMI shielding materials. [ABSTRACT FROM AUTHOR]

A coupled moving beam-pulley vibration model is established for a typical serpentine belt drive system with three pulleys. Both general and explicit expressions for the eigenvalue sensitivity to the structural parameters of system are derived by perturbation analysis. Then the rule of the first-order natural frequency changes with system structural parameters is studied with the eigenvalue sensitivity verified by finite difference method. [ABSTRACT FROM AUTHOR]

The recovery of high-value carbon fibers from carbon fiber-reinforced polymer (CFRP) composites is essential for ensuring a sustainable future. In this work, a simple and eco-friendly approach was presented for the chemical recycling of anhydride-cured epoxy-based CFRP composites with a mixed solution of monoethanolamine (MEA) and potassium hydroxide (KOH). In this solvent catalyst system, the resin matrix was decomposed by cleaving the ester bonds. Thus, a high CFRP composite decomposition ratio of 99% was achieved at ∼160 °C within 60 min under ambient pressure. The recovered carbon fibers (CFs) had a clean surface and retained more than 95% of their original stiffness and strength. Moreover, one of the highlights of this process was that the excess MEA solvent and degraded epoxy resin (DER) were recovered from the degraded organic products (DOP) by simple distillation. The DER was reused in combination with the original epoxy resin system to prepare new resin material with good mechanical properties, forming a closed-loop chemical recycling route. The advantages of this method include facile reaction conditions, near-complete recovery of CFs and solvent, and the absence of harmful solid waste, demonstrating that this recycling process has a high degree of environmental friendliness. [Display omitted] [ABSTRACT FROM AUTHOR]

Environmentally friendly thermal interface materials (TIMs) with bidirectional high thermal conductivities have aroused considerable interests for addressing the heat dissipation issue in integrated circuits. Although graphene-based TIMs exhibit excellent in-plane thermal conductive performance, their through-plane thermal conductivity is commonly less than 3 Wm−1K−1 owing to the vast interfacial phonon scattering, significantly limiting their practical applications. In this study, a strategy aimed at building TIMs with controllable heat transfer pathways both along the in-plane and through-plane directions is proposed by incorporating micron-diamonds (MDs) in graphene nanoplatelets/nanofibrillated cellulose (GNPs/NFC) composite film via a facile and green self-assembly method. The morphology of the obtained MDs@GNPs/NFC composite film can be precisely tailored from a hierarchical structure to a 3D solid foam-like structure to tailor heat transfer paths. By adjusting the loading and particle size of MDs, a through-plane thermal conductivity of 8.85 Wm−1K−1 was achieved accompanied with a simultaneously high in-plane thermal conductivity of 32.01 Wm−1K−1. The excellent bidirectional thermal conductive performance is integrated with high-efficiency Joule heating capability, outstanding nonflammability, as well as superior electromagnetic shielding performance, showing a promising future in advanced electronic devices. [Display omitted] [ABSTRACT FROM AUTHOR]

Solar steam generation (SSG) has been considered as a promising method to produce fresh water from seawater. Due to high light absorption and excellent chemical stability, carbon nanotube (CNT) has been widely used for SSG. However, it is still challenge to simultaneously realize high water evaporation rate and energy efficiency for CNT based solar steam generator. Herein, ultralight anisotropic Ti 3 C 2 T x MXene/carbon nanotube (A-Ti 3 C 2 T x /CNT) aerogels are designed and fabricated for highly efficient SSG. The combination of CNT and Ti 3 C 2 T x MXene endows the hybrid aerogel with high light absorption and effective localized surface plasmon resonance (LSPR), resuting in enhanced light-to-heat conversion efficiency. The porous structure of aerogel leads to multiple scattering and absorption, further contributing to the photothermal conversion process. Moreover, the low thermal conductivity of aerogel structure effectively reduces the heat loss to environment. Through tailoring the anisotropic channel, the A-Ti 3 C 2 T x /CNT hybrid aerogel with average channel size of 80 μm possesses most efficient water transport due to the capillary effect and formation of intermediate water. Therefore, the A-Ti 3 C 2 T x /CNT hybrid aerogel exhibits high average light absorption of 95.68% in the wavelength range of 200–2500 nm, excellent water evaporation rate of 2.10 kg m−2 h−1 under 1 sun irradiation (1 kW m−2) with a high energy efficiency of 93.4%, and remarkable durability with 7 days continuous water evaporation. The A-Ti 3 C 2 T x /CNT hybrid aerogel also shows high resistance to salt crystallization due to its high salt transport flux of 1.90 kg m−2 h−1. This work offers a prospective strategy for constructing highly efficient solar steam generator with stable performance for practical application in seawater desalination. A Short Summary: Through combining carbon nanotube (CNT) with high light absorption and Ti 3 C 2 T x MXene with excellent light-to-heat conversion efficiency, ultralight anisotropic Ti 3 C 2 T x MXene/carbon nanotube hybrid aerogels are fabricated for highly efficient solar steam generation. The obtained aerogel with suitable pore structure exhibits a high light absorption ability of up to 95.68% in the wavelength range of 200–2500 nm, an excellent water evaporation rate of up to ∼2.10 kg m−2 h−1 under 1 sun irradiation (1 kW m−2)) with a high energy efficiency of 93.4%, and a remarkable durability of up to 7 days. [Display omitted] [ABSTRACT FROM AUTHOR]

With an excellent combination of high strength, lightweight, and thermal stability, carbon fiber-reinforced polymer (CFRP) composites are ideal for applications in various demanding fields. The global consumption of CFRP composites continues to increase, and it is estimated that approximately 3000 tonnes of CFRP waste are generated annually. Mostly, the CFRP composites can be classified into two categories: thermoset composites and thermoplastic composites. However, the recycling of industrial thermoset composites is a daunting challenge due to their highly cross-linked thermosetting polymer matrix. In this study, an innovative strategy was developed for recycling amine-cured CFRP composites with a binary alkali catalytic system of monoethanolamine containing 10 wt% potassium hydroxide under facile conditions. The degradation ratio of CFRP composites reached 98.82% after processing at 160 °C in 90 min. The surface of recovered carbon fibers (CFs), as observed by SEM and AFM, appeared smooth, and there was a slight increase in the surface wettability as tested by dynamic contact angle measurements. Furthermore, the use of XPS demonstrated some surface oxidation, while single fiber filament testing suggests a small decrease in the tensile strength of 6.5%. • A binary alkali solvent system of monoethanolamine containing 10 wt% potassium hydroxide successfully degraded amine-cured CFRP composites under facile condition. • The method had the recovery yield of CFRP composites reached up to 98.82% after processing at 160 ℃ in 90 min. • The recovered CFs were clean with approximately 93% of original tensile strength. • The recovered CFs had better surface wettability than that of virgin CFs. [ABSTRACT FROM AUTHOR]

Helicobacter pylori (H. pylori) infection has increasingly been a serious problem worldwide. The H. pylori infection can result in a series of stomach diseases including gastric carcinoma. There are two specific virulence genes (cagA and vacA) of H. pylori that are closely related to the occurrence of gastric cancer, and the common molecular detection methods (PCR, qPCR) are not suitable for high-screening test due to the requirement of expensive instruments and well-trained personals. Herein, we develop a rapid visual assay based on loop-mediated isothermal amplification (LAMP) for detecting H. pylori and its major virulence genes (cagA , vacAs1 and vacAm1) to guide clinical treatment for H. pylori infection. In this research, a fluorescent LAMP assay was established by optimizing the indicator of MnCl 2 -Calcein, so that the resulted color and fluorescence changes could be utilized to perform the visual detection for H. pylori and its virulence genes with high sensitivity (10−3 ng/μL). The proposed LAMP assay is simple, fast (30 min) and capable in providing more sensitive results than traditional methods in the test of 46 clinical biopsy samples. By detecting the three virulence genes together, we can profile the infection risk of the patients, and discuss the correlation among the genes. Moreover, the method could be used to diagnose virulently infected individuals and benefit the eradication of H. pylori in early warning for gastric cancer. [Display omitted] • A visual diagnostic of fluorescent LAMP for H. pylori and virulence genes was developed in one analysis step. • An orthogonal test was designed to optimize the LAMP reaction conditions. • The infection risk of 46 patients was finally profiled by detecting the three virulence genes. [ABSTRACT FROM AUTHOR]

[Display omitted] • The free-standing, monolithic and anisotropic graphite networks were constructed by a two-stage, economy, facile expansion process. • The sensitivity of the sensors/switches can be accurately tailored. • The wireless monitoring of human movement was realized by integrating the sensors/switches with microelectronic components. Highly sensitive strain sensors and switches are essential components to wearable electronics in many emerging applications such as personal health monitoring, human–machine interaction, smart robots and intelligent control system. Herein, we report a new highly-anisotropic graphite framework (HAGF) for creating strain sensors and switches with high flexibility, stretchability and sensitivity. The highly anisotropic three-dimensional (3D) graphite structure was fabricated via a facile, low-cost and scalable expansion of commercially-available graphite papers. By controlling the orientation structure and thickness of HAGF, the contact area and switchable conduction path can be tailored to create strain sensors and switches based on HAGF/PDMS composites to achieve a tunable gauge factor between 1.3 and 379, an ultra-high ON/OFF ratio in the order of 1035 with tunable critical switching strain (8 % ∼ 50 %), an excellent long-term repeatability of over 1000 cycles at a peak strain of 50 %, and a stretchability up to 100 %. The potentials of the new sensors and switches are demonstrated by pairing them with the smartphone for tracking and recognition of human motions, offering a new solution to a wide range of portable devices and mobile applications. [ABSTRACT FROM AUTHOR]

• MXene nanoparticles were successfully deposited onto the CF surface via EPD technic for the first time. • MXene-CFRP composites enhanced 53%, 22.2%, and 29.2% in ILSS, flexural strength, and single fiber tensile strength. • The interfacial strengthen mechanism was proposed as mechanical interlocking and hydrogen bonding. To improve the weak fiber-matrix interface of carbon fiber composites, two-dimensional transition metal carbides or nitrides of MXene (Ti 3 C 2 T x) nanosheets were introduced onto the surfaces of carbon fiber (CF) through electrophoretic deposition (EPD) technology for the first time. The MXene deposited CF was further infiltrated with epoxy resin by vacuum-assisted resin infusion (VARI) to fabricate CFRP composites. Results indicated that the MXene nanoparticles deposited on the surfaces of CF could significantly enhance fiber surface energy and wettability as well as surface roughness, which in turn remarkably increased the interfacial strength and flexural properties of fiber-resin. The MXene/oxidised CF/epoxy composites showed a 53% improvement in interlaminar shear strength (ILSS), a 22.2% enhancement in flexuous strength, and a 29.2% increment in monofilament tensile strength than non-functionalised specimens. This simple and effective strategy provided a promising approach for effective CFRP modification and continuous industrial production. [Display omitted] [ABSTRACT FROM AUTHOR]

Optimization design of the structures and thicknesses of the sound packages is performed for automotive interior acoustic performance and lightweight characteristics. A SEA model of the car was created, and its interior noise of the automobile was predicted and validated at speed of 120 km/h. The contributions of some major subsystems to interior noise were calculated at 120 km/h. Both of major characteristic indices including interior SPL and total weight of sound packages are selected to evaluate automotive interior acoustic performance and lightweight characteristics, and four selected optimization parameters are structures and thicknesses of the sound package of firewall and front floor. The problem of multiple performance indices is simplified into single performance index by using grey relational grade. The optimal combination of sound package parameters is determined by employing grey relational analysis method. Furthermore, the validation tests show that the values of interior SPL and overall weight of sound packages decrease by 1.31% and 60.36%, respectively. Also, the comparison of the overall SPL for automotive interior noise experiments between original and optimized structures and thicknesses of the sound packages shows that automotive interior acoustic performance is obviously improved from 200 Hz to 10,000 Hz. Therefore, it is demonstrated that it is an effective way to deal with optimization problems by using the presented approach in this research. [ABSTRACT FROM AUTHOR]

By reference to GB 15742, horn acoustic tests on thirteen passenger cars of different types are conducted, and the suitable evaluation terms of horn sound quality are determined according to the characteristics of horn sound samples. A subjective evaluation program suiting to paired comparison method is developed, and a test of the subjective preference of horn sound is carried out on 22 participants with the reliability and consistency of test data analyzed. Finally, the main psychoacoustic objective parameters of each sample are calculated, and a preference evaluation model describing the correlation between subjective preference evaluations and psychoacoustic objective parameters is established with algorithms of linear correlation and multi linear regression. The results indicate that the subjective/objective preference model is nonlinear, and the sharpness and linear sound pressure level, in particular the former, are the key factors affecting the people's favor and acceptance of horn sound quality. [ABSTRACT FROM AUTHOR]

Abstract: The generation and refinement of finite element mesh is an important task of FEA (Finite Element Analysis). The conventional methods have weak adaptability to the shape of field domain and make computers suffer heavy workload. Based on fractal theory, the CIFS (Composite Iterated Function System) is established which can be used in the generation and refinement of finite element mesh. A new FEM (Finite Element Method) is hereby formed, by which the processing speed can be improved, the memory can be saved and the good universality and adaptability to boundary shape can be obtained. It also opens a new way to FEA. [Copyright &y& Elsevier]