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Fluorinated molecules are widely used in pharmaceutical and agrochemical industries. Multifluoroalkyl-containing compounds have attracted increasing attention for their unique ability to alter the activity of drugs and bioactive molecules. Herein, we report an efficient Rh(III)-catalyzed, redox-neutral, C–H multifluoroalkenylation of benzamides with multifluoroalkenes, which provides a versatile protocol for accessing a wide range of multifluoroalkenylated arenes. [ABSTRACT FROM AUTHOR]

Nanoparticles (PANI/DKL-NPs) were prepared by self-assembly via π–π interactions between conducting polyaniline (PANI) and demethylated Kraft lignin (DKL) molecules. The resulting PANI/DKL-NPs are interspersed with polyaniline molecules of controllable content and rich mesoporous structures, which provide high ionic proximity and fast electron transfer, leading to excellent capacitance properties of the composites and high energy density when assembled into supercapacitors. [Display omitted] Redox-active lignin rich in phenolic hydroxyl groups is an ingenious charge storage material. However, its insulating nature limits the storage/release of electrons and requires the construction of electron transfer channels within it. Herein, nanoparticles (PANI/DKL-NPs) are prepared by co-assembly via π–π interactions between conducting polyaniline (PANI) and demethylated Kraft lignin (DKL) molecules for the first time, and rapid electron transfer inside DKL is achieved. The co-assembled PANI/DKL-NPs consist of interpenetrating structures of PANI and DKL at the molecular scale, and the content of PANI molecules interspersed within them is controllable. Meanwhile, the extensive and abundant mesoporous structure in nanoscale PANI/DKL-NPs facilitates ion transport and electron storage. Based on this favorable microstructure, the specific capacitance of PANI/DKL-NPs at 1 A·g−1 is as high as 532 F·g−1, which is 780 % and 90.68 % higher compared to DKL-NPs and PANI-NPs, respectively. Meanwhile, the rate performance of PANI/DKL-NPs is significantly enhanced than that of DKL-NPs (33.11 %) and comparable to that of PANI-NPs (more than 69 %). Furthermore, the symmetric supercapacitor (PANI/DKL-NPs//PANI/DKL-NPs) assembled from it achieves a high energy density of 27.49 Wh·kg−1 at 400 W·kg−1 power density, and superb flexibility and mechanical stability. Therefore, the co-assembly of DKL and PANI will effectively stimulate the energy storage potential of lignin, providing a practical pathway to promote the development of biopolymers in energy storage. [ABSTRACT FROM AUTHOR]

Introduction: Ventricular assist devices (VADs) are considered an effective treatment for patients with advanced heart failure, while complications associated with blood damage remain a burden. Structure design innovation has the potential to reduce hemolysis and improve hemocompatibility. Methods: In this research, a novel mixed‐flow blood pump that integrates structural features of the axial and centrifugal VADs was proposed. The pump consists of an inducer, a mixed impeller supported by two ceramic pivot bearings, and a volute. The flow field and laminar viscous shear stress were analyzed by the in silico simulation. The hydraulic and hemolytic performance were evaluated in vitro by using a 3D printed pump. Results: The flow field distribution showed that streamlines in the connection area were smoothly transitioned through structural integration and no irregular flow occurred in the entire flow channel. The axial blades work as a fluid accelerator (generating 18.56% of the energy), and the centrifugal blades provide the main pressure head. The proportion of fluid inside the pump exposed to low laminar viscous shear stress (<50 Pa) and high laminar viscous shear stress (>150 Pa) was 99.02% and 0.03%, respectively. The in vitro hemolysis test results showed that the NIH (Normalized Index of Hemolysis) value of the mixed pump is 0.0079 ± 0.0039 g/100 L (n = 6). Conclusion: It can be concluded that the mixed flow structure is effective at improving hydraulic performance, eliminating flow disturbance, and minimizing shear stresses. This novel pump design is expected to provide a new direction for the development of next‐generation VADs. [ABSTRACT FROM AUTHOR]

The electromagnetic interference and heat accumulation pose a significant challenge for the traditional high-density single-function electromagnetic shielding materials in advanced flexible integrated electronics. Herein, nano-silver flakes (AgNFs, reflective layer), MXene (Ti 3 CNTx, loss layer) and silver nanowires (AgNWs, heat conduction and shielding layer) constructed ordered multi heterogeneous layers high-performance flexible electromagnetic shielding functional composites (AMA composites). Especially the composites exhibited outstanding electromagnetic interference shielding efficiency (EMI SE) of 70.96 dB even with an extremely thin coating of 25 g/m2, which is 350% higher than that of the commercial standard (20 dB). It is worth noting that the AMA composites also possessed certain qualities such as superior thermal conductivity, flame retardancy, chemical resistance, high-temperature resistance (25 °C–100 °C), and mechanical properties (tensile strength of 44.4 MPa, Young's modulus of 0.6 GPa). The composites display application possibilities in highly integrated advanced flexible electronic products and wearable electronic devices, as well as provide structural design and research ideas for the usage of a new MXene material (Ti 3 CNTx) in electromagnetic shielding composite materials. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Graphene/silver nanoparticles coating exhibited timely transfer of electrons and heat due to the 3D electric conductive network. • The aluminum film played the dual functions of electromagnetic interference shielding and heat transfer. • The material showed excellent electrical conductivity and electromagnetic interference shielding effectiveness of 4431 S/m and 92.29 dB, respectively. • The material exhibited outstanding mechanical properties with tensile strength of 32 MPa and elongation at break of 6.65%. Rubber and plastic are widely acted as substrates in flexible electromagnetic shielding (EMS) materials. However, these materials have several drawbacks in practical applications, such as potential environmental concerns and difficulties in degrading. In this work, a biodegradability paper-based material composed of electromagnetic wave loss layer (graphene/ silver nanoparticles (AgNPs) coating) and reflective layer (aluminum film layer) was successfully fabricated. The electromagnetic wave loss layer constructed three-dimensional (3D) electric conductive network to facilitate the timely transfer of electrons and heat energy obtained from electromagnetic waves. Meanwhile, the reflective layer received electrons and heat from the electric conductive network and make a small quantity of transmission wave back to the wave loss layer. The resulting material exhibited an ultrahigh electromagnetic interference shielding effectiveness (EMI SE) of 92.29 dB within 8–13 GHz, electrical conductivity of 4431 S/m, mechanical properties with a tensile strength of 32 MPa and elongation at break of 6.65%. Compared to the traditional EMS materials, the composite material integrated with excellent EMI SE, heat transfer performance, and weatherability, which has potential applications in microelectronics, high integrated circuits, and flexible electronic fields. [ABSTRACT FROM AUTHOR]

• LDAOs are rich in quinone groups. • The redox of quinone groups realizes charge storage. • The feasibility of LDAOs as renewable charge storage materials was investigated. • Lignin structure significantly affects its energy storage performance. Lignin-derived aromatic oligomers (LDAOs) are the primary components of lignin depolymerization products. They are typically utilized as renewable crosslinking agents or resin materials with a considerably lower application value than aromatic monomers. Notably, LDAOs are rich in quinone groups, which enable storage and release of charges. In this work, the feasibility of LDAOs as renewable charge storage materials was investigated. LDAOs were first reacted with formaldehyde to generate a synthetic polymer (SP-AOF) via a phenol-formaldehyde condensation reaction. SP-AOF was subsequently incorporated with reduced graphene oxide (rGO), namely rGO/SP-AOF. As expected, the hybrid electrode exhibited high specific capacitance (250 F/g), which was approximately three times higher than that of rGO (87 F/g). This was due to the presence of quinone groups in SP-AOF, which could contribute to the overall capacitance with pseudocapacitance. Moreover, the hybrid electrode was able to deliver a high specific capacitance of 210 F/g even at a high specific current of 10 A/g. 1H−13C heteronuclear single quantum coherence nuclear magnetic resonance (2D HSQC NMR) and phosphorus nuclear magnetic resonance spectroscopy (31P NMR) analyses revealed that SP-AOF displayed higher quinone content (3.76 mmol/g) than commercially available lignin (organosolv and alkali lignin), which resulted in higher energy storage performance. This study provides a promising strategy for the utilization of aromatic oligomers as raw materials to manufacture high-performance lignin-derived energy storage materials. [ABSTRACT FROM AUTHOR]

The construction of thermally conductive pathways to improve the thermal conductivity of the thermal interface materials (TIMs) is highly demanded due to the expanding trend of miniaturization, integration, and high-power of microelectronics, whereas the present TIMs could hardly provide the satisfying heat management performance. Herein, we report a progressive 3D self-assembly strategy for the fabrication of a composite film with excellent flexibility and thermally conductivity. Hexagonal boron nitride (BN)-OH is cross-linked with lignin nanoparticle (LNP) by borax and assembled onto cellulose nanofibrils (CNF), after further freeze-drying and pressing the composite film is thus formed. SEM analysis revealed that the BN-LNP thermally conductive pathways were successfully formed, and LNP acted as the cross-linking point of BN-OH. The 50 wt% filler loaded BN-LNP/CNF composite (BN-LNP50) exhibited a through-plane thermal conductivity of 2.577 W/mK, while this feature for the pure CNF film was only 0.413 W/mK, revealing an improvement of ~524%. It is worth noting that at the same filler content, the composite loaded with non-cross-linked BN/LNP mixture presented a much lower thermal conductivity (1.224 W/mK) compared to that was loaded with BN-LNP (2.084 W/mK). Particularly, the BN-LNP50 was thermally decomposed at 230 °C, demonstrating an increasement of 30% compared with the pure CNF film. Overall, this study provides an effective approach to fabricate BN-related thermally conductive materials with improved thermal management capacity. Image 1 [ABSTRACT FROM AUTHOR]

• DESs can affect rheological behaviors and imbibition performance of CFFs via intermolecular interactions. • HBDs in DESs play a vital role in regulating CFF properties. • DESs increase the viscosity, shear resistance and viscoelastic modulus of CFFs. • DESs can promote the imbibition efficiency and accelerate the imbibition kinetics. Fracturing fluid properties are closely related to the oil recovery of unconventional reservoirs. In the meantime, deep eutectic solvents (DESs) have provided a new method to improve the properties of clean fracturing fluids (CFFs) due to their low-toxicity raw materials and mild synthesis conditions. In this work, DESs were developed as the enhancers to intensify rheological characteristics and spontaneous imbibition performance of CFFs. The adjustment of hydrogen bond donors (HBDs) can effectively regulate the rheological characteristics of CFFs. The DES composed of choline chloride (ChCl) and malonic acid (MA) can significantly increase the viscosity of CFF from 38.1 mPa·s to 60.1 mPa·s, the shear resistance and viscoelastic modulus were both improved. The interactions between HBDs and sodium p -toluenesulfonate (TsONa) anion has an influence on the electrostatic shielding of TsONa anion for OAHSB, which further determines the strength of micelle networks. For the spontaneous imbibition of CFFs, DESs improved the imbibition efficiency from 33.0% in 98 h to 40.1–47.2% in 78–90 h through the reduction of oil–water interfacial tension and oil viscosity, change of oil-contacting surface wettability and the increase of core porosity and permeability. The DESs here provide a novel strategy to enhance CFF properties in an environmentally friendly and efficient way. [ABSTRACT FROM AUTHOR]

• Recoil pressure is the key factor for spattering and expansion of molten pool. • Intensity of vortex generated at groove bottom is greater than that at the side. • More recast layer and redeposition of melt result in a poor surface roughness of groove. • Surface roughness of groove gradually decreased with increasing laser moving speed. Laser surface texturing is considered as a novelty and feasible technology to fabricate some micro-feature due to the non-contact, high precision and processing efficiency. However, it is difficult to deeply understand the material removal mechanism and predict the surface topography due to a confined heat-affected zone and extremely short time in the laser machining process. In this research, based on the mixed phase theory and level-set method, a modified heat-mass transfer and hydrodynamic model was proposed for deeply analyzing the influence of various physical factors such as recoil pressure, buoyancy, surface tension, gravity and thermal-mass transport on the material removal and micro-texture topography evolution at a mesoscale level. The analysis of hydrodynamic behaviors and temperature fields of the molten pool indicated that the melts sputtering and molten pool expansion caused by the recoil pressure was the dominant factor responsible for micro-texture formation during laser action. The reflux induced by the surface tension and gravity as well as the residual effect of the melts flowing upward were the main factors of the occurrence of a vortex during the molten pool cooling. Finally, the effects of laser parameters on the micro-feature topography were discussed based on the experiments and simulation model. The diameter and depth of the hole as well as the width and depth of the groove gradually increased with increasing frequency and pulse duration. The laser moving speed had less effect on the width of the groove, but it had great effect on the surface roughness of the groove. This work can be beneficial to understand the material removal mechanism and provide a guide for the parameters optimization of laser processing at a mesoscale level. [Display omitted] [ABSTRACT FROM AUTHOR]

Comprehensively understanding the albumin and fibrinogen adsorption behaviors is of fundamental significance for blood-contacting devices to effectively prevent the proteins adsorption. First, a controllable superhydrophobic surface presented great repellence to different liquids with water contact angle 165.2°, plasma contact angle 154.8° and blood contact angle 152.1°. Secondly, the albumin and fibrinogen adhesion tests indicated that the pure titanium surface was fully covered by the proteins layer while only a small amount of the proteins adhered to the superhydrophobic surface. Furthermore, the extended Derjaguin-Landau-Verwey-Overbeek (XDLVO) model was built by considering the Lifshitz-van der Waals (LW), the Lewis acid-base (AB) and the electrostatic double-layer (EL) interactions, the positive value of total interaction energy profile suggested that an overall repulsive interaction between the protein molecules and superhydrophobic surface happened at a small separation distance. Finally, the hollow tubes with inner superhydrophobic surface were implanted into carotid artery of rabbits for two weeks. The content of N element measured by EDS mapping provide a new evidence that superhydrophobic surface owns a great resistance of the proteins absorption, and no thrombosis or blood cells adhered to the superhydrophobic surface. This research revealed the mechanism that superhydrophobic modification could effectively prevent the adsorption of plasma proteins, which could provide some theoretical basis to help design the blood-contacting devices with great hemocompatibility. [Display omitted] • A controllable superhydrophobic surface is fabricated by laser process and chemical treatment. • Anti-proteins adsorption mechanism is revealed by the protein adhesion tests and XDLVO theory. • In vivo animal test verifies the anti-proteins adsorption behavior of superhydrophobic surface. [ABSTRACT FROM AUTHOR]