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With the increasing consumer focus on automotive safety, Autonomous Emergency Braking (AEB) systems, recognized as effective active safety technologies for collision avoidance and the mitigation of collision-related injuries, are gaining wider application in the automotive industry. To address the issues of the insufficient working reliability of AEB systems and their unsatisfactory level of accordance with the psychological expectations of drivers, this study proposes an optimized second-order Time to Collision (TTC) safety time algorithm based on the motion state of the preceding vehicle. Additionally, the study introduces a safety distance algorithm derived from an analysis of the braking process of the main vehicle. The safety time algorithm focusing on comfort and the safety distance algorithm focusing on safety are effectively integrated in the time domain and the space domain to obtain the safety time–safety distance fusion algorithm. A MATLAB/Simulink–Carsim joint simulation platform has been established to validate the AEB control strategy in terms of safety, comfort, and system responsiveness. The simulation results show that the proposed safety time–safety distance fusion algorithm consistently achieves complete collision avoidance, indicating a higher safety level for the AEB system. Furthermore, the application of active hierarchical braking minimizes the distance error, at under 0.37 m, which meets psychological expectations of drivers and improves the comfort of the AEB system. [ABSTRACT FROM AUTHOR]

Considering the requirements pertaining to the trafficability of off-road vehicles on rough roads, and since their roll stability deteriorates rapidly when turning violently or passing slant roads due to a high center of gravity (CG), an efficient anti-slip control (ASC) method with superior instantaneity and robustness, in conjunction with a rollover prevention algorithm, was proposed in this study. A nonlinear 14 DOF vehicle model was initially constructed in order to explain the dynamic coupling mechanism among the lateral motion, yaw motion and roll motion of vehicles. To acquire physical state changes and friction forces of the tires in real time, corrected LuGre tire models were utilized with the aid of resolvers and inertial sensors, and an adaptive sliding mode controller (ASMC) was designed to suppress each wheel's slip ratio. In addition, a model predictive controller (MPC) was established to forecast rollover risk and roll moment in reaction to the change in the lateral forces as well as the different ground heights of the opposite wheels. During experimentation, the mutations of tire adhesion capacity were quickly discerned and the wheel-hub drive motors (WHDM) and ASC maintained the drive efficiency under different adhesion conditions. Finally, a hardware-in-the-loop (HIL) platform made up of the vehicle dynamic model in the dSPACE software, semi-active suspension (SAS), a vehicle control unit (VCU) and driver simulator was constructed, where the prediction and moving optimization of MPC was found to enhance roll stability effectively by reducing the length of roll arm when necessary. [ABSTRACT FROM AUTHOR]

The effects of laser welding parameters on the interface microstructure of AZ31B magnesium alloy and 304 stainless steel were investigated. After welding, a scanning electron microscope and ultra-depth of field microscope were used to observe the microstructure of the welded material, to analyze the effects of power on the interface morphology. The simulation of laser welding of magnesium and steel was carried out by the COMSOL software. The results showed that when the power was 15 W–20 W, the temperature did not reach the melting point of magnesium alloy, there was MgO at the welding, and the interface had poor connection strength. When the power was 35 W–50 W, the temperature reached or even exceeded the boiling point of magnesium alloy, and the interface formed hot cracks, pores, and oxides and had poor joint strength. When the power was 25 W–30 W, the temperature was between the melting point and boiling point of magnesium, and the interface had excellent connection strength. [ABSTRACT FROM AUTHOR]

• The magnesium alloy and 304 stainless steel were successfully joined via nanosecond pulsed laser welding. • Highest tensile shear force of 298.7 N was obtained at the speed of 30 mm/s. • Three fracture modes produced at various welding speeds were clarified. • The welding temperature field of magnesium/steel joint was simulated. Nanosecond pulse laser welding was performed on AZ31B magnesium alloy and 304 stainless steel to investigate the impact of welding speed on the joining process. The temperature field of the magnesium/steel laser welding process was simulated using COMSOL software. The findings revealed that a welding speed of 10 mm/s resulted in significant spattering and larger porosity defects in the joint due to excessive heat input. However, when the welding speed was increased to 30 mm/s, these defects disappeared, and the porosity decreased to a minimum, leading to an increased bonding area at the interface. As the speed increased, the heat input decreased, making it more challenging for the porosity to escape from the molten pool and resulting in the formation of larger pores. The shear force test results indicated that the highest shear force was 298.7 N at a welding speed of 30 mm/s. The reduction in porosity and greater penetration depth of the magnesium alloy contributed to the desired mechanical performance. Additionally, the fracture modes were classified as button pullout failure (BPF), base material tearing failure (BTF), and interface failure (IF). The outermost weld seam served as the initial fracture path for both BPF and BTF modes, with BTF ultimately fracturing in the steel base material during tearing. Oxide inclusions, porosity, and the angle of distortion contributed to the fracture path of IF. [ABSTRACT FROM AUTHOR]

Lithium-ion batteries have received considerable attention as energy storage tool for modern-life equipments. However, drawbacks like low electric conductivity and volume expansion are the obstacles that hinder its application. To solve these problems, we developed a facile method using waste eggshell as hard template to reduce its particle size and change its morphology by simple hydrothermal process. Then, by utilizing waste paper, conductive paper (CP) current collector with graphene and multiwalled carbon nanotube implanted was prepared and combined with MnO2 anode material. The composite anode shows extraordinary electrochemical performances like much smaller impedance, high reversible capacity of 1767/1762 mAh/g even after 200 cycles at 100 mA/g, superior rate performance, etc. Compared with anode using metal current collectors, this composite anode will reduce weight and can be generalized to other high energy storage applications. Our environment-friendly method has far-reaching referential significance to other active materials and battery systems. A composite electrode, with δ -MnO2 as active material and conductive paper as current collector, has been synthesized and used in lithium-ion battery. Waste eggshell and waste paper were used in the synthetic process to protect environment. The electrode is much lighter and has much better electrochemical performances. This method can be generalized to other active materials and battery systems. [ABSTRACT FROM AUTHOR]

Abstract In this manuscript, the longest O/N and S/N atoms containing heteroacenes (tetraazatetraoxodecacene (TAOD) and tetraazatetrathiodecacene (TATD)) with ten linearly fused rings have been synthesized and fully characterized. The X-ray crystal structures show that O/N atoms containing TAOD exhibits a linear structure, while S/N atoms containing TATD bends in S atom containing heterorings. Obviously, TAOD shows a higher fluorescence quantum yield in solution than that of S atom containing compound TATD. By simple reprecipitation method, TAOD and TATD self-assembly into different microstructures with microwires and microrods, respectively, which demonstrate distinctive non-linear optical properties depending on the orientation of transition dipoles. Graphical abstract Image 1 Highlights • The longest O/N (TAOD) and S/N (TATD) atoms containing heteroacenes with ten linearly fused rings were successfully prepared. • TAOD and TATD show different photophysical and electrochemical properties. • The microcrystals of TAOD and TATD exhibit distinctive non-linear optical properties depending on the orientation of transition dipoles. [ABSTRACT FROM AUTHOR]

Novel pyridine-ring containing twisttetraazaacene 9,14-diphenylpyreno[4,5- g ]isoquinoline ( 1 ) and its full-carbon derivative 9,14-diphenyldibenzo[ de , qr ]tetracene ( 2 ) have been synthesized and fully characterized. Studies showed that compound 1 could identify picric acid (PA) over other common nitro compounds with high selectivity and sensitivity. Upon the addition of PA, the emission peak of compound 1 in CH 3 CN was red shifted from 447 to 555 nm with a fluorescence quenching efficiency as high as 95%, the detection limit was calculated to be 2.42 μM, while its full-carbon derivative ( 2 ) could not exhibit this kind of performance. The possible mechanism with the enhanced PA detection efficiency in pyridine-ring containing twisttetraazaacene ( 1 ) than its full-carbon derivative ( 2 ) was also investigated. [ABSTRACT FROM AUTHOR]

Superparamagnetic Fe 3 O 4 supraparticles@MIL-100(Fe) core–shell nanostructure microspheres were successfully constructed by a facile step-by-step method. The polyacrylate formed in situ during the process of the preparation of Fe 3 O 4 supraparticles not only acted as a stabilizer on the Fe 3 O 4 nanoparticles surface, but also played a crucial role as a “bridge” in the initial stage of the framework components selectively assembly on the Fe 3 O 4 supraparticle surfaces. The structure and composition of the obtained microspheres were characterized by SEM, TEM, DLS, XRD, FTIR, and TG analysis. The MPMS results revealed that the introduction of the MOF shells can inhibit the interplay among the neighboring Fe 3 O 4 supraparticles while an external magnetic field applied. The well-dispersed microspheres are biocompatible, which endow the microspheres great potential in drug targeting applications with enhanced efficiency. [ABSTRACT FROM AUTHOR]

Uniform magnetite mesocrystals were fabricated by solvothermal treatment of ferrous chloride in ethylene glycol in the presence of sodium hydroxide. The formation mechanism of magnetite mesocrystals in ethylene glycol was deduced by a time-dependent experiment. [ABSTRACT FROM AUTHOR]

Abstract: Spherical Fe3O4 nanocrystal clusters were prepared via a simple solvothermal method using FeCl2·4H2O and NaOH as starting materials. When sodium acetate (NaAc) was added into the reaction system, the final products turned from sphere to cube. The as-prepared clusters are uniform in size. The possible mechanism was proposed to elucidate the changes of the clusters shape. The chemical compositions were characterized by X-ray diffraction (XRD). The morphology was determined by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The magnetic properties were investigated on a superconducting quantum interference device (SQUID) magnetometer. [Copyright &y& Elsevier]

Abstract: Superparamagnetic magnetite microspheres with a hydrophobic surface were successfully prepared through a simple solvothermal method based on hydrolysis of iron–oleate complex in diphenyl ether in the presence of oleic acid as the ligands. The microspheres size and size distribution were analyzed by a laser diffraction particle size analyzing method using ZETASIZER. The morphology and crystalline structure of the products were characterized using transmitting electron microscopy (TEM), scanning electron microscopy (SEM), X-Ray diffraction (XRD), and the magnetic property was studied by a Quantum Design MPMS SQUID. TEM and SEM images showed that as-prepared spherical nanostructures are of about 140nm in sizes, which self-assembled by many 10nm primary magnetic nanoparticles. The XRD analysis revealed that the magnetic microspheres are composed of magnetite. The magnetic measurements demonstrated that the spherical nanostructures are superparamagnetic at room temperature with no magnetic remanence and coercive force. In addition, the microspheres can be well dispersed in various non-polar solvents due to their surfaces capped of hydrophobic surfactants in situ. [Copyright &y& Elsevier]

Abstract: Magnetite nanoparticles have been successfully synthesized in liquid polyols at elevated temperature. Polyol solvent plays a crucial role in determining the morphology and colloidal stability of the resulting particles. The structure and morphology of the nanoparticles were studied using XRD, TEM, SAED, TGA and FTIR. The magnetic properties of the samples were measured using physical properties measurement system (PPMS) of Quantum Design. The results show that as-prepared magnetite nanoparticles are monodisperse, highly crystalline and superparamagnetic at room temperature. The nanoparticles can be easily dispersed in aqueous media and other polar solvents due to coated by a layer of hydrophilic polyol ligands in situ. This approach provides a facile route to prepare magnetite nanoparticles. [Copyright &y& Elsevier]

Abstract: A facile polyol process was established to prepare superparamagnetic Fe-doped ZnO nanoparticles in a liquid polyol using Fe(acac)3 and Zn(acac)2 as precursors and triethylene glycol as the solvent. Scanning electron microscopy (SEM) images showed that as-prepared nanoparticles are uniform in size. X-ray diffraction (XRD) analysis revealed that the nanoparticles are of wurtzite structure without an impure phase. The successful doping of the Fe element into the ZnO host was evident by XRD lines shifting and energy dispersive X-ray spectroscopy (EDS) results. Magnetization measurements demonstrated that the Fe-doped ZnO nanoparticles were superparamagnetic at room temperature. [Copyright &y& Elsevier]

Abstract: Fe3O4@ZnO core–shell structured nanoparticles have been synthesized by a simple one-pot sequential polyol process. The nanoparticles have been investigated by powder X-ray diffraction (XRD), transmission electron microscope (TEM), energy-dispersive X-ray spectrometer (EDS) and physical properties measurement system (PPMS) of Quantum Design. [Copyright &y& Elsevier]

Engineered Cementitious Composites (ECC) utilize the bridging effect of high toughness fibers to improve the brittle failure of concrete materials, achieve the effective control of cracks in cementitious materials, and significantly improve the deformation capacity. In view of the multi-stage crack-blocking effect of different fibers incorporated in ECC materials, 91 ECC specimens of steel-polypropylene hybrid fiber by mixing steel fiber (SF) and polypropylene fiber (PPF) into cement-base are made in this paper. The specimens are tested in compression, tensile, bending and damping properties, respectively, which is of great significance to study the response of ECC structures under the earthquake action. The effects of the volume content of SF and PPF on the mechanical properties of ECC are studied in this paper. The results show that the cube specimen has better ductility than the prismatic specimen under monotonic compression, and there is no obvious brittle failure. With the increase of the volume content of SF to PPF, the compressive strength and elastic modulus of hybrid fiber ECC gradually increase, while the corresponding strain and axial compressive toughness gradually decrease; the tensile strength and tensile modulus increase, while the bending strength and damping ratio decrease. According to the test results, constitutive models of monotonic and repeated loading of hybrid fiber ECC suitable for finite element (FE) analysis are proposed. This investigation provides a theoretical basis and an experimental reference for further study of steel-polypropylene hybrid fiber ECC. • Steel fiber and polypropylene fiber are mixed as hybrid fiber of ECC. • The mechanical properties of ECC are investigate. • Volume content of steel-polypropylene hybrid fiber has influence on concrete material. • The hybrid fiber ECC cube has better ductility than that of prismatic. • Constitutive models of hybrid fiber ECC are suitable for finite element analysis. [ABSTRACT FROM AUTHOR]

Liquid hydrogen storage is an important way of hydrogen storage and transportation, which greatly improves the storage and transportation efficiency due to the high energy density but at the same time brings new safety hazards. In this study, the liquid hydrogen leakage in the storage area of a hydrogen production station is numerically simulated. The effects of ambient wind direction, wind speed, leakage mass flow rate, and the mass fraction of gas phase at the leakage port on the diffusion behavior of the liquid hydrogen leakage were investigated. The results show that the ambient wind direction directly determines the direction of liquid hydrogen leakage diffusion. The wind speed significantly affects the diffusion distance. When the wind speed is 6 m/s, the diffusion distance of the flammable hydrogen cloud reaches 40.08 m, which is 2.63 times that under windless conditions. The liquid hydrogen leakage mass flow rate and the mass fraction of the gas phase have a greater effect on the volume of the flammable hydrogen cloud. As the leakage mass flow rate increased from 5.15 kg/s to 10 kg/s, the flammable hydrogen cloud volume increased from 5734.31 m3 to 10,305.5 m3. The installation of a barrier wall in front of the leakage port can limit the horizontal diffusion of the flammable hydrogen cloud, elevate the diffusion height, and effectively reduce the volume of the flammable hydrogen cloud. This study can provide theoretical support for the construction and operation of hydrogen production stations. [ABSTRACT FROM AUTHOR]

With the rapid development of hydrogen energy worldwide, the number of hydrogen energy facilities, such as hydrogen refueling stations, has grown rapidly in recent years. However, hydrogen is prone to leakage accidents during use, which could lead to hazards such as fires and explosions. Therefore, research on the safety of hydrogen energy facilities is crucial. In this paper, a study of high-pressure hydrogen jet flame accidents is conducted for a proposed integrated hydrogen production and refueling station in China. The effects of leakage direction and leakage port diameter on the jet flame characteristics are analyzed, and a risk assessment of the flame accident is conducted. The results showed that the death range perpendicular to the flame direction increased from 2.23 m to 5.5 m when the diameter of the leakage port increased from 4 mm to 10 mm. When the diameter of the leakage port is larger than 8 mm, the equipment on the scene will be within the boundaries of the damage. The consequences of fire can be effectively mitigated by a reasonable firewall setup to ensure the overall safety of the integrated station. [ABSTRACT FROM AUTHOR]

Chalcogenide cathodes with multi‐electron transfer characteristics are indispensable to aluminum‐ion batteries (AIBs). Nevertheless, their grievous capacity degradation and sluggish reaction kinetics remain fundamental challenges for the practical application. Herein, a Cu2S/Ni3S2 multiphase structure within the metal‐organic frame (MOF) derived carbon decoration layer (CNS@MC) is constructed to elevate the intrinsic electronic properties of chalcogenide cathode and realize high‐performance AIBs. The existence of outer carbon layer and strong orbital interaction at inner heterointerfaces eliminates the bandgap and arises more electrons at Fermi level, efficiently reducing the energy barrier for electron transfer and achieving high reactivity within cathodes. The CNS@MC also presents a strong electronic interaction with active solvent groups, which is beneficial to capture Al3+ and facilitate the three‐electron charge‐storage reactions. Experimental results demonstrate that the tailored CNS@MC cathode possesses superior redox kinetics due to the sufficient surface area and rapid Al‐ion diffusion during cycling. Meanwhile, the robust CNS@MC delivers ultra‐high electrochemical stability (131.1 mAh g−1 over 3500 cycles) with high coulombic efficiency and outstanding rate performance. This work offers new opportunities for optimizing the intrinsic properties of the chalcogenide electrodes based on MOF derivatives and heterostructure, providing novel thoughts for designing high‐performance AIBs. [ABSTRACT FROM AUTHOR]

Aqueous static zinc–iodine batteries attract tremendous attention because of their abundant reserves of iodine, nonflammable electrolyte, and facile assembly. Currently, scientific challenges for static zinc–iodine batteries include self‐discharge and sluggish kinetics. Herein, a lithiation approach for the iodine host to suppress the shuttle effect and catalyze iodine conversion is reported. Through regulating the d‐ and p‐band center and lowering the I−/I0 conversion barrier, Li+ intercalation into VS2 reinforces interaction with I3− and achieves catalytic conversion of iodine, ameliorating self‐discharge, and accelerating kinetics. Zinc–iodine batteries featuring LiVS2 as the iodine host reach a high iodine utilization, high Coulombic efficiencies, and a long cyclic lifespan. Notably, the performance enhancement mechanism is the thermodynamically favorable iodine conversion reaction, inhibition of the I3− appearance, and promotion of I3− consumption due to the Li+ insertion. The findings provide fundamental insights into tackling issues of static zinc–iodine batteries. [ABSTRACT FROM AUTHOR]

Effectively increasing the length of N‐heteroacenes is highly desirable because such materials could have great potential applications in organic optoelectronics. In this review we summarize the recent progress in the construction of larger N‐heteroacenes based on the use of phenazinediamine and its analogues as building blocks to react with different kinds of ortho‐diketones (or tetraketones) or ortho‐dihalides through condensation or coupling reactions. In addition, the potential applications of the corresponding N‐heteroacenes are also presented. [ABSTRACT FROM AUTHOR]

The development of safe, cheap, and environmentally friendly advanced rechargeable batteries with high energy density are one of the most pressing tasks for today's energy crisis. With the advantages of low cost, abundant reserves, and high‐level safety, rechargeable aluminum ion batteries are considered ideal candidates for next‐generation energy storage batteries in the context of large‐scale energy applications. Relevant knowledge of energy storage materials and electrolytes, which possess close connection in between, is undeniably crucial for such research, while ironically, most attention is attracted to merely one element alone, especially the energy storage materials involving micro/nanomaterials. In this review, we focus on cathode materials matching with various electrolyte systems for rechargeable aluminum batteries and manage to provide new ideas for the preparation methods of high‐efficiency electrochemical energy storage materials, with future outlooks in this field. [ABSTRACT FROM AUTHOR]

The Ti3C2Tx MXene with surface functional groups complexing Mn4+ (Mn–Ti3C2Tx) was prepared for the cathode of aqueous zinc batteries. The electrode reaction is confirmed as the Zn2+/H+ co-insertion compensated by the Mn4+/Mn2+ redox. The Mn4+-loading modification boosts the Zn2+ storage due to the enhanced Zn2+ adsorption possibility. [ABSTRACT FROM AUTHOR]

Concrete-filled steel tube (CFST) columns are widely used in structures where high bearing capacity and ductility are crucial. They offer several advantages over conventional steel or concrete columns, such as a high strength-weight ratio, better ductility, and increased resistance to buckling and compression. Also, seismic damage in CFST columns primarily occurs within the plastic hinge region at their base. Therefore, by improving the ductility specifically in this plastic hinge region, the seismic resilience of CFST columns can be significantly enhanced. In this paper, the use of steel-polypropylene hybrid fiber engineered cementitious composites (HECC) in the plastic hinge region of square CFST columns is proposed to improve their hysteretic performance. This paper presents an experimental study of the hysteretic behavior with three different local HECC-enhanced CFST (LHECFST) columns. Based on the test results, modeling was performed using ABAQUS, and the reliability of the FE model was verified. Following this, FE models with smaller HECC pouring height gradients were developed, and these CFST columns were parametrically analyzed. The results show that the seismic performance of CFST columns is improved by local enhancement with HECC. The pouring of HECC will reduce the slope of the peak load descending stage of the CFST column. In addition, the formulas for calculating the peak load of LHECFST columns with different axial compression ratios and HECC pouring heights were developed and the accuracy was verified by contrasting the data. • Hysteresis tests on concrete-filled steel tube (CFST) columns were performed. • The validation data were established by finite element analysis. • Engineered cementitious composites (ECC) reduce damage in plastic hinge region. • The deterioration of peak loads in CFST columns with ECC localized pouring is slow. • Methods are proposed for calculating the peak load of two-material CFST columns. [ABSTRACT FROM AUTHOR]

• A lightweight onboard measurement system for micro-UAV swarms based on sensor fusion and neural networks is proposed. • A collaborative relative positioning method based on DGO and DEKF is developed. • The system is implemented on a 150 g micro-UAV platform, demonstrating high precision and real-time capability. In recent years, the swarm of micro Unmanned Aerial Vehicles (micro-UAVs) is becoming a research hotspot. As the basis of swarm autonomous flight, traditional relative positioning methods typically rely on external base stations or onboard sensors of high power consumption, the vast majority of which are not feasible on resource-constrained micro-UAVs flying in a complex environment. This article proposes a lightweight relative positioning system implemented on a micro-UAV platform weighing 150 g. We have developed a distributed graph optimization (DGO) scheme fusing the results of the onboard Ultra-Wideband (UWB) module, camera, and inertial sensors. A Delay Extended Kalman Filter (DEKF) is utilized to mitigate communication delays and enhance accuracy. This scheme enables micro-UAVs to collaboratively compute the relative position graph in real-time. Through real-world experiments, our system has achieved a relative positioning accuracy of 0.167 m, exhibiting significant potential for future swarm applications. [ABSTRACT FROM AUTHOR]

The kinetics of the ring-opening polymerization of ε-caprolactone with butane-1,4-diol as the initiator and 1,5,7-triazabicyclo[4.4.0]dec-5-ene as catalyst were examined. A highly efficient and controllable polymerization of ε-caprolactone occurred with an activation energy of 22.5 kJ·mol–1 , which is much lower than that observed with butan-1-ol as the initiator (39.5 kJ·mol–1). An intramolecular hydrogen-bonding-assisted mechanism is proposed to explain this lowering of the activation energy. [ABSTRACT FROM AUTHOR]

Abstract Owing to their special optical and chemical properties, polymers with helical nanostructures are good candidates for constructing building blocks for various applications in analytical and biomedical science. While the chirality of conjugated polymers has been well studied, there are few reports on the chirality of polyurethanes (PUs). In particular, direct morphological observations of their chiral nanostructures are rare. In this work, PUs were synthesized using isosorbide (ISO) and isomannide (ISOM), derived from renewable feedstocks, as chiral building segments and 1,4-phenylenediisocyanate (4,4′-MDI) and para -phenylenediisocyanate (PPDI), which have rigid structures, as hard segments. The molecular structures and thermal properties of the PUs were characterized, as well as the nanostructures formed following their deposition on solid surfaces. Polymers with 4,4′-MDI segments had plate-like structures, whereas those with PPDI segments had rod-like structures, with ISO-PPDI-PU and ISOM-PPDI-PU exhibiting helical nanostructures, as confirmed by transmission electron microscopy and atomic force microscopy. Graphical abstract ISO-PPDI-PU polymers were synthesized and self-assembled to helical nanostructures, which were confirmed by atomic force microscopy. Image 1 Highlights • Polyurethanes with various chiral units and hard segments were fabricated. • The chiral building blocks were derived from renewable feedstocks. • The nanostructures formed by the polymers depended on the type of hard segment. • The formation of helical nanostructures was confirmed by atomic force microscopy. [ABSTRACT FROM AUTHOR]

Fucoidan is a kind of natural water-soluble fucose-rich sulfated polysaccharide with promising applications in the food and pharmaceutical industry. However, the traditional methods for fucoidan recovery from aqueous solution are expensive, time-consuming, and environmentally unfriendly. In this work, polyethyleneimine functionalized magnetite nanoparticles (PEI-MNPs) with well-defined core-shell structures were prepared by a Layer-by-Layer (LbL) approach using sodium tripolyphosphate (STPP) as a cross-linker. The as-prepared PEI-MNPs showed improved adsorption capability towards fucoidan at pH 4–8 due to the high density of cationic groups on the surfaces and the absence of internal pores. It was found that the adsorption process of fucoidan onto PEI-MNPs can reach to equilibrium in 50 min at room temperature. The maximum q e derived from the Langmuir isotherm at room temperature was 169.1 mg per g at a pH of 7. A selective fucoidan capture over a model protein BSA can be realized by adjusting pH (6–8) and salt concentration (0.5–2.5 M). The PEI-MNPs loading with fucoidan can be isolated from the final products by a neodymium magnet and regenerated by 4 M NaCl solution as stripping reagent. Therefore, this novel kind of PEI-MNP could be a promising candidate for highly efficient and recyclable recovery of fucoidan from an aqueous solution. [Display omitted] • A novel type of PEI-MNP nanoadsorbents was fabricated for fucoidan recovery. • PEI-MNP nanoadsorbents exhibit excellent adsorption performance towards fucoidan. • PEI-MNPs could be efficiently separated from the final products and repeatedly used. [ABSTRACT FROM AUTHOR]

Abstract: Three novel heterocyclic compounds containing one (M1) or two (isomers M2 and M3) benzimidazole units have been synthesized and fully characterized. The isomers M2 and M3 could be easily separated by column chromatography. Studies showed that the decrease of intermolecular π‐π stackings could enhance the fluorescence intensity of target compounds obviously. The single‐site compound M1 shows the lowest fluorescent quantum yield (ΦM1=0.013) in CH2Cl2 than that of the double‐site isomers M2 (anti‐type, ΦM2=0.148) and M3 (syn‐type, ΦM3=0.053). Electroluminescent performances of M2 and M3 in organic light‐emitting diodes were studied. As expected, M2 exhibits more than 2 times higher current efficiency than M3 with M2 showing a maximum current efficiency of 7.8 cd/A as compare to 3.6 cd/A for M3. [ABSTRACT FROM AUTHOR]

• Heterostructured g-C 3 N 4 /Ti 3 C 2 T x endows electrode with enhanced structural stability and fast charge transfer. • The heterostructured g-C 3 N 4 /Ti 3 C 2 T x delivers superior aluminum-storage performance. • The charge-discharge mechanism for g-C 3 N 4 /Ti 3 C 2 T x is reversible intercalation of chloroaluminate anions. [Display omitted] As a compelling complement to lithium batteries, rechargeable aluminum batteries (RABs) have attracted considerable attention because of abundant natural resources, high volumetric capacity, and safety property of aluminum metal. However, the deployment of RABs is hampered by the lack of favorable cathodes with high capacity and rapid kinetics. To address the long-unresolved issue of aluminum-storage capacity and rate, here we design a heterostructured g-C 3 N 4 /Ti 3 C 2 T x hybrid which offers a conductive supporting framework to maintain structural integrity and accelerate electronic transport. The energy storage mechanism of the heterostructured g-C 3 N 4 /Ti 3 C 2 T x cathode was demonstrated as the reversible intercalation of AlCl 4 − during cycling. Moreover, the battery-capacitance model mechanism in the heterostructured g-C 3 N 4 /Ti 3 C 2 T x hybrids may accelerate the kinetics of the electrode reactions. Furthermore, DFT calculations certify that heterostructured g-C 3 N 4 /Ti 3 C 2 T x possesses enhanced electrical conductivity and Al trapping capability. Accordingly, the heterostructured g-C 3 N 4 /Ti 3 C 2 T x cathode affords RABs with an excellent Al-storage property (237 mAh g-1 at 0.5 A g-1) and considerable rate capabilities (174 mAh g-1 at 4 A g-1) among state-of-the-art cathode materials for aluminum batteries. [ABSTRACT FROM AUTHOR]

Abstract: Biodegradable poly(l-lactide) (PLLA) has been covalently grafted onto the surface of magnetic multiwalled carbon nanotubes (m-MWCNTs) by in-situ ring-opening polymerization of lactide. The content of grafting PLLA can be controlled by adjusting the feed ratio of monomer to m-MWCNTs. FT-IR and Raman spectroscopy confirm that PLLA have been covalently attached to the sidewalls of m-MWCNTs. Thermal gravimetric analysis (TGA) indicates that the composites of PLLA grafted m-MWCNTs have a polymer weight percentage of ca. 25.6–33.7wt%. The scanning eletron microscopy (SEM) and transmission electron microscopy (TEM) are utilized to image the PLLA grafted m-MWCNTs, showing relatively uniform polymer layer coated on the surface of m-MWCNTs. The composites of PLLA grafted m-MWCNTs exhibit superparamagnetic behavior at room temperature and are aligned under a low magnetic field. [Copyright &y& Elsevier]

Abstract: The composites based on poly(l-lactide) (PLLA) and two kinds of multi-wall carbon nanotubes (Fe3O4/MWCNTs and MWCNTs) were prepared by solution casting. The molecular level interactions, thermal, magnetic, mechanical properties and dispersion of MWCNTs in polymer matrix were investigated by Raman spectroscopy, differential scanning calorimetry (DSC), magnetic property measure system (MPMS), tensile test and scanning electron microscopy (SEM). The results of Raman spectra revealed the doping-type molecular interaction between filler and polymer matrix. Compared to the pure PLLA, the glass transition temperature (T g) of MWCNTs/PLLA and Fe3O4/MWCNTs/PLLA composites increased from 50 to 51°C and from 50 to 58°C, respectively. The Fe3O4/MWCNTs/PLLA composite was supermagnetic at room temperature. The Young''s modulus, elongation rate at break and tensile strength of Fe3O4/MWCNTs/PLLA composite were improved compared to the neat PLLA and MWCNTs/PLLA composite. Fe3O4/MWCNTs were finely dispersed in the PLLA matrix. The results present potential applications for the biodegradable Fe3O4/MWCNTs/PLLA composite in tissue engineer, biomedicine and bone fixation. [Copyright &y& Elsevier]