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The extraction of keratin from discarded feathers for the preparation of poly (vinyl alcohol) (PVA) ionic conductive hydrogels with enhanced mechanical properties shows promise for applications in green flexible electronics. Here, we first extracted feather keratin (FK) from duck feather fibers using the lactic acid/ l -cysteine deep eutectic solvents. Subsequently, the composite ionic conductive hydrogel composed of FK, PVA, and CaCl 2 was constructed by a one-pot freeze-thawing strategy. The introduction of FK resulted in a denser structure of the fabricated hydrogel, which significantly enhanced its mechanical properties, including high elongation at break of 639.3%, high breaking strength of 270 kPa, and durable fatigue resistance. Impressively, the hydrogel-based wearable strain sensor demonstrated high strain sensing sensitivity (GF = 1.26), wide strain detection range (5%–200%), fast response, and stable reliability, enabling it to accurately monitor and distinguish the difference in electrical signals generated by large and tiny human motions. This work provides a reliable method for the green extraction of FK and the design of high-performance PVA hydrogel-based flexible electrical devices. [Display omitted] • FK was extracted from feathers using a novel deep eutectic solvent. • PVA based ionic conductive hydrogels were constructed by a one-pot freeze-thawing strategy. • FK enhanced mechanical properties and ionic conductivity of hydrogels. • The hydrogel demonstrated superior strain sensing performance. • The hydrogel sensors are suitable for human motion monitoring. [ABSTRACT FROM AUTHOR]

Abstract Tremendous attention has been paid to the structure and properties of silk fibroin/sodium alginate (SF/SA) composite films. However, there is no report devoted to study the formation of hydrogen bonds and their effects on the structures and properties. Herein, SF/SA blends with different mass ratios were obtained and the technic of Gaussian multi-peaks-fitting of Fourier transform infrared spectrum (FTIR) was used to analyze their hydrogen bonds. From the results, the existence of the intermolecular and intramolecular hydrogen bonds was manifested, and the relative strength of the intermolecular hydrogen bond enhanced with the increase of SA content. The contribution of the intermolecular hydrogen bonding was as follows: OH⋯O (ether) > OH ... π > OH⋯N. Meanwhile, the increase of intermolecular hydrogen bonding led to the increase of apparent viscosity of the SF/SA blend solutions. Moreover, the relationship between the hydrogen bond and properties (e.g, crystallinity, thermal stability, mechanical properties, morphology and etc.) of SF/SA composite films with different mass ratios were analyzed in detail. Graphical abstract Image 1 Highlights • Gaussian multi-peaks-fitting of FTIR was used to analyze the hydrogen bonding of SF and SA blends. • The hydrogen bonds of the blends with different ratio were quantitatively analyzed and clarified. • Effect of the SA on the structure and properties of the SF/SA composites was analyzed based on hydrogen bonds. [ABSTRACT FROM AUTHOR]

Scavenging energy stored at the water/solid interface into electrical power by the natural water evaporation process provides a promising method to supply sustainable electricity for self-powered electronics. The main barriers constraining its applications are the limited materials availability and ambiguous underlying mechanisms, detrimental to the improvement of output power. Herein, we report a highly flexible and efficient evaporation-induced electricity generator (EIEG) that dexterously exploits the directional water capillary flow inside the silicon nanowires (SiNWs) mesh nanopores. Benefiting from the large surface/volume ratio and high surface potential of nanostructured SiNWs mesh film, an EIEG continuously delivers a high open-circuit voltage of ~1.5 V and a maximum power density of over 160 μW·cm−3, which surpasses the analogous flexible EIEGs. Moreover, the correlation between the output power and capillary flow direction, diffusion length, and velocity as well as the species and ionic strength of various liquids have been systematically explored to identify the mechanism underlying the power generation. This study not only provides an in-depth understanding of water/solid interactions but also spikes a green technique to fabricate flexible generators that tap energy from the copious water reservoir. A highly flexible and efficient evaporation-induced electricity generator (EIEG) that dexterously exploits the directional water capillary flow inside the silicon nanowires (SiNWs) nanopores has been developed. This study not only provides an in-depth understanding of water/solid interactions but also spikes a green technique to fabricate flexible generators that tap energy from the copious water reservoir. [Display omitted] • A highly flexible and efficient evaporation-induced electricity generator (EIEG) that dexterously exploits the directional water capillary flow inside the silicon nanowires (SiNWs) nanopores is developed. • An EIEG continuously delivers a high and continuous open-circuit voltage of ~1.5 V and a maximum power density of over 160 μW·cm−3. • The EIEG exhibits outstanding flexibility, rendering it portable and suitable for self-powered electronics. [ABSTRACT FROM AUTHOR]

Silk fibroin aerogel generally suffers from weak mechanical properties, which limits its application in the high-performance materials. Hence, we develop a non-alkali urea degumming strategy for the raw silk to improve the mechanical properties of silk fibroin aerogel. The silk fibroin aerogel with a low density of 13.43 ± 0.77 mg/cm3 was fabricated successfully via silk fibroin dissolution, dilution and freeze-drying. We systematically analyze the solution properties of silk fibroin prepared via alkali degumming and non-alkali degumming. Meanwhile, the morphology and structure of aerogel are characterized by scanning electron microscopy, X-ray diffraction spectroscopy and Gaussian multi-peaks-fiting technique of infrared spectrum. Moreover, we investigate the effects of non-alkali degumming method on the mechanical properties and thermal stability of aerogels. The results manifest that the non-alkali urea degumming process reduces damage to silk fibroin, leading to the stable three-dimensional skeleton structure of the prepared aerogels. Furthermore, compared with the silk fibroin aerogel prepared by alkali degumming, the silk fibroin aerogel prepared by non-alkali degumming has higher crystallinity and content of β-sheet structure, resulting in the better mechanical properties and thermal stability. This work may pave the way for the fabrication of silk fibroin aerogel materials with high mechanical properties. Image 10047 • Non-alkali urea degumming process was used to prepare high-performance fibroin aerogel. • The fibroin aerogel exhibits excellent mechanical properties and thermal stability. • The mechanism of urea degumming to improve the performance of fibroin aerogel was systematically studied. [ABSTRACT FROM AUTHOR]

This allergic reaction to snake venom was described to occur in patients after recurrent exposure through bites in amateur and professional snake handlers, which might be underestimated and contribute to fatal snakebites in victim, independently from the toxicity of the venom itself. Few allergens were identified from snake venoms by normal SDS-PAGE, which cannot separate the snake venom completely. In the present study, we identified nine potential allergens by two-dimensional (2D) electrophoresis followed by immunoblotting (named as allergenomics) in Protobothrops mucrosquamatus venom. By multidimensional liquid chromatography-ion trap mass spectrometry (MDLC-ESI-LTQ-MS/MS) analysis, six allergens showed sequence similarity to snake venom serine proteinases. Other allergens showed sequence similarity to snake venom metalloproteinase. These allergic reactions to snake venom allergens might contribute to fatal snakebites in victim, independently. [ABSTRACT FROM AUTHOR]

Understanding the mechanisms of supercritical CO 2 heat transfer deterioration (HTD) has significant importance for ensuring the safety and reliability of supercritical Brayton cycles. Therefore, the effects of mass flux, wall heat flux, and tube diameters on the heat transfer characteristics of supercritical CO 2 inside vertical tubes are studied using experimental and numerical methods. Results indicate that the heat transfer performance is positively influenced by an increase in mass flux and heat flux, as well as a decrease in tube diameter. When HTD occurs, the overall heat transfer performance is indeed significantly compromised. When the bulk fluid temperature exceeds T pc , the thermal acceleration effect amplifies the mainstream velocity, stabilizing the Kelvin-Helmholtz instability between the pseudo-two-phases, thereby causing a new type of HTD that is named Type II HTD in this paper. The so-called post-dryout HTD occurs when the bulk temperature surpasses T +, causing a complete transition from pseudo-liquid to pseudo-gas state and resulting in a pseudo-single-phase flow. The heat transfer capability of the low-density and low-thermal-conductivity pseudo-gas diminishes as the temperature rises, leading to post-dryout HTD. The present work explains the mechanisms of two types of HTD and highlights the similarities between subcritical boiling and supercritical pseudo-boiling flow structures. This study also establishes a theoretical foundation for understanding pseudo-two-phase flow patterns during pseudo-boiling. [ABSTRACT FROM AUTHOR]

• New mechanism for supercritical water HTD is proposed. • Coupling effects of nanoparticles and corrugated tubes on HTD are investigated. • Mitigation effect of nanoparticles on "HTD cycles" is investigated. • Mechanism for suppression of HTD by nanoparticles and corrugations is investigated. When faced with high thermal loads, the dramatic variations in supercritical water (SCW) thermophysical properties can lead to heat transfer deterioration (HTD). Therefore, the present paper first proposes a new mechanism of HTD based on the pseudo boiling theory, and then numerically investigates the mitigation effects of nanoparticles and corrugations on the HTD. By the investigation of SCW in vertically upward smooth tube, the mechanism study illustrates that the pseudo film with the characteristics of low turbulence intensity and thermal conductivity induces the HTD, and the pseudo two-phase flow instability dominates the growth and dissipation of pseudo film. With the help of nanoparticles and corrugations, the wall temperature has a maximum decrease of 348 K, the wall temperature peak mitigation ratio was 33.5%, and the maximum heat transfer enhancement is 164%. Since the corrugations within the corrugated tube (CT) does not change the growth rate of pseudo film, "HTD cycles" occurs in the CT with large corrugation pitch and further deteriorates the overall heat transfer performance. By the inhibition of pseudo film growth and enhancement of gas-like SCW thermal conductivity, the coupling effect of nanoparticles and corrugations can effectively suppress the HTD as well as "HTD cycles". [ABSTRACT FROM AUTHOR]

Exosomes are extracellular vesicles with a variety of biological functions that exist in various biological body fluids and exert their functions through proteins, nucleic acids, lipids, and metabolites. Recent discoveries have revealed the functional and biomarker roles of miRNAs in urological diseases, including benign diseases and malignancies. Exosomes have several uses in the diagnosis, treatment, and monitoring of urological diseases, especially cancer. Proteins and nucleic acids can be used as alternative biomarkers for detecting urological diseases. Additionally, exosomes can be detected in most body fluids, thereby avoiding pathogenesis. More importantly, for urological tumors, exosomes display a higher sensitivity than circulating tumor cells and tumor-derived DNA in body fluid biopsies because of their low immunogenicity and high stability. These advantages have made it a research hotspot in recent years. In this review, we focus on the biological characteristics and functions of exosomes and summarize their advantages and the latest progress in the diagnosis and treatment of urological diseases. • The urinary system is an important excretion pathway of human metabolites. • Exosome plays an important role in the development and progression of urological diseases. • Exosomal cargoes could be used as biomarkers and targets of novel therapies of urological diseases. • The research and exploration to realize the clinical transformation of the medical value of exosome are on the way. [ABSTRACT FROM AUTHOR]

Filling materials and fabrics with radiative heating properties have promising applications on personal thermal management and demonstrate a series of advantages in reducing the energy consumption and improving the convenience and lightweight of warm clothing. However, the fluffiness of the down fibers is usually decreased after the functional modifications and coating, resulting in the deterioration of warmth retention and appearance. Although the warmth retention of the down fibers can be improved by decoration of Zr (Ⅳ), it is not a good way to address the problems originated from the low-loading and poor washability of Zr (Ⅳ) due to the weak interactions between the down fibers and Zr (Ⅳ). Herein, we report a novel and facile layer-by-layer (LBL) self-assembly strategy to fabricate the Zr (Ⅳ) modified down fibers with high Zr (Ⅳ) loading, excellent radiative heating performance and washability. The surface temperature of Zr (Ⅳ) modified down fibers is increased by 3.75 °C after being exposed to the infrared radiation source, which exceeds the state-of-the-art chemical modified down fibers. More importantly, the radiative heating performance of Zr (Ⅳ) modified down fibers deteriorates less than 5% after 8 wash cycles, exhibiting good washability. The excellent radiative heating performance is attributed to the robust coordinate bonds between phytic acid and zirconium ions. In addition, the prepared down fibers have natural fluffy velvet flowers and high fluffiness without any broken fibers owing to the moderate LBL self-assembly process. This work paves the way for the low-damage functional modifications of the down fibers and other protein materials. • A facile layer-by-layer self-assembled Zr (Ⅳ) modified down fibers is reported. • Zr (Ⅳ) modified down fibers show high fluffiness and Zr (Ⅳ) loading. • Zr (Ⅳ) modified down fibers has good radiative heating performance. • Zr (Ⅳ) modified down fibers exhibit good washability. [ABSTRACT FROM AUTHOR]

With the rapid development of information technology and electronics, the traditional textiles hardly fulfill the requirements of wearable electronics. Multifunctional textile-based electronics integrated with energy storage, joule heating, electromagnetic interference (EMI) shielding and sensing has become a favorable solution. Herein, a scalable spray-coating and dip-coating strategy is developed to fabricate the multifunctional reduced graphene oxide/Ti 3 C 2 T x MXenes decorated cotton fabrics. The RGO/MXene modified fabrics show hydrophilic surface, high electrical conductivity, good flexibility and breathability. In addition, the RGO/MXene modified fabrics demonstrate excellent electrochemical performance, and the assembled all-solid-state supercapacitors show one of the highest specific capacitances of 383.3 F g−1 (258 mF cm−2). More importantly, the RGO/MXene fabrics show distinctive negative resistance variation and high sensitivity when they are applied as the strain sensors to detect the human motions including the bending of finger, elbow, knee and swallowing process. Moreover, the RGO/MXene fabrics show good joule heating and EMI shielding performance. This work may shed light on cost-effective but high-performance textile-based strain sensors, EMI shielding and electrochemical energy storage devices, and paves the way for the development of multifunctional wearable electronics. Unlabelled Image • RGO/MXene@cotton fabric (RMC) exhibited high specific capacitance of 383.3 F g−1. • RMC-based strain sensors demonstrated distinctive negative resistance variation. • RMCs showed good joule heating (ΔT=36.0 °C). • RMCs exhibited good electromagnetic interference shielding performance (29.04 dB). [ABSTRACT FROM AUTHOR]