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A disposable screen-printed electrode modified with composite material of graphene aerogel, AuNPs, Nafion and PSA aptamer were fabricated for PSA detection. [Display omitted] • High-performance PSA detection based on SPE and electrochemical detection. • Introduce 3D graphene aerogel and AuNPs to highly boost detection sensitivity. • Highly sensitive and accurate detection of PSA with low LOD over 0.05 to 50 ng∙mL−1. Prostatic cancer threatens the lives and health of numerous male patients all over the world. As a single-chain glycoprotein, prostate specific antigen (PSA) can be used to perform prostate cancer screening. At present, there are still problems such as time-consuming and low sensitivity in hospital detection. At the same time, electrochemical immunosensor technology has received a lot of attention due to its benefits, including high sensitivity, good selectivity, low usage and cost, and so on. Electrocatalysts are typically used to build electrochemical immunosensors for signal amplification in the recent years to realize sensitive detection of cancer biomarkers such as PSA. In recent years, three-dimensional nanomaterials have been widely used in the study of electrocatalysts, but the study of the sensitivity for PSA detection is still very scarce. The present work reported the application of a 3D graphene aerogel(GA)/AuNPs/Nafion electrochemical platform for highly sensitive PSA quantification. The electrochemical immunosensor has been designed by immobilizing aptamers on the screen-printed electrode (SPE) surface modified by GA/AuNPs/Nafion. Scanning electron microscopy (SEM), Raman spectra, and electrochemical characterization demonstrated the successful combination of GA/AuNPs/Nafion/SPE. Based on electrochemical impedance spectroscopy (EIS), the proposed immunosensor has demonstrated excellent electrochemical performance, exhibiting sensitive and stable responses for electrochemical detection of PSA ranging from 0.05 to 50 ng∙mL−1 with a limit of detection (LOD) of 0.0306 ng∙mL−1. This study has great potential application in PSA detection and provides a valuable reference for point-of-care testing (POCT) of prostate cancer. [ABSTRACT FROM AUTHOR]

V 3 O 7 ·H 2 O possesses the merit of high specific capacitance, but weakness of cycling stability and low conductivity inhibit its application for energy devices, which requires the addition of carbon materials like carbon nanotubes (CNT) or graphene with properties of high conductivity and brilliant cycling stability to obtain high-performance composites. Since CNT or GO-based binary V 3 O 7 ·H 2 O materials have been rarely studied with limited specific capacitance, we developed a novel, highly porous V 3 O 7 ·H 2 O nanobelts/CNT/reduced graphene oxide (V 3 O 7 ·H 2 O/CNT/rGO) ternary composite with a three-dimensional (3D) hierarchical micro-structure by a single step, facile hydrothermal process and self-assembly method with outstanding electrochemical performances. During the hydrothermal process, CNT-anchored V 3 O 7 ·H 2 O nanobelts have been incorporated on the surface of rGO through in situ growth with preferred orientation, forming a 3D hierarchical porous structure composed mostly of mesopores and exhibiting enlarged specific surface area up to 53.7 m 2 ·g −1 . The well-designed V 3 O 7 ·H 2 O nanobelts also display excellent adhesion with CNT/rGO, which leads to reduced resistance resulted from the synergistic effect of pseudocapacitors (V 3 O 7 ·H 2 O nanobelts) and electric double-layer capacitors (EDLCs) (CNT/rGO) and large specific area with sufficient active sites ensure the composite to brilliant capacitive behavior. Applied to SCs, the ternary composite exhibits outstanding electrochemical performance with higher specific capacitance (685 F·g −1 at 0.5 A·g −1 ), higher energy density (34.3 W·h·kg −1 ) and extremely prominent cycle stability (99.7% of initial specific capacitance after 10,000 cycles) compared to those of most similar binary materials. Results suggest that the V 3 O 7 ·H 2 O/CNT/rGO ternary composite is a promising candidate for electrode materials applying to high-performance supercapacitors. [ABSTRACT FROM AUTHOR]

Carbon fiber cloth/epoxy resin composites with different layer orientation angles were prepared to evaluate electromagnetic shielding properties in the X band. The results showed that the electrical conductivity, dielectric constant and shielding effectiveness of composites decreased with increase in layer angle. Absorbed power had the maximum value (0.577) at 49.60° with sample thickness 4.00 mm. After using carbonyl iron powder as the radio wave absorber, both conductivity and shielding effectiveness improved when layer angle was beyond 10.06°. Reflected power decreased while absorbed power increased with increase in layer angle and their variation rates decreased. Structure and function integrated shielding products made of these composites can be used to get the highest shielding effectiveness or highest absorbed power with designed layer angles. [ABSTRACT FROM AUTHOR]

Carbon fiber felt–glass fiber felt/epoxy resin multilayer composites with different layer angle were prepared to evaluate electromagnetic shielding properties in the X band. Comparison of composites with or without adding carbonyl iron powder was made in electric properties and shielding properties. Carbon fiber felt–glass fiber felt/epoxy resin multilayer composite can get a high shielding effectiveness (76.3 dB) at a suitable thickness (4.00 mm) when layer angle is close to 0°. Shielding effectiveness decreases rapidly with increase in layer angle and power constituent parts have different variations. Variations in dielectric constant and magnetic permittivity were found after adding carbonyl iron powder. Use of carbonyl iron powder can improve shielding effectiveness and absorbed power when layer angle is beyond 35°. Carbonyl iron powder-carbon fiber felt–glass fiber felt/epoxy resin composite can get high absorbed power (62.6%) when layer angle is about 45°. [ABSTRACT FROM AUTHOR]

Trimodal Al alloy (AA) matrix composites consisting of ultrafine-grained (UFG) and coarse-grained (CG) Al phases and micron-sized B 4 C ceramic reinforcement particles exhibit combinations of strength and ductility that render them useful for potential applications in the aerospace, defense and automotive industries. Tailoring of microstructures with specific mechanical properties requires a detailed understanding of interfacial structures to enable strong interface bonding between ceramic reinforcement and metal matrix, and thereby allow for effective load transfer. Trimodal AA metal matrix composites typically show three characteristics that are noteworthy: nanocrystalline grains in the vicinity of the B 4 C reinforcement particles; Mg segregation at AA/B 4 C interfaces; and the presence of amorphous interfacial layers separating nanocrystalline grains from B 4 C particles. Interestingly, however, fundamental information related to the mechanisms responsible for these characteristics as well as information on local compositions and phases are absent in the current literature. In this study, we use high-resolution transmission electron microscopy, energy-dispersive X-ray spectroscopy, electron energy-loss spectroscopy, and precession assisted electron diffraction to gain fundamental insight into the mechanisms that affect the characteristics of AA/B 4 C interfaces. Specifically, we determined interfacial structures, local composition and spatial distribution of the interfacial constituents. Near atomic resolution characterization revealed amorphous multilayers and a nanocrystalline region between Al phase and B 4 C reinforcement particles. The amorphous layers consist of nonstoichiometric Al x O y , while the nanocrystalline region is comprised of MgO nanograins. The experimental results are discussed in terms of the possible underlying mechanisms at AA/B 4 C interfaces. [ABSTRACT FROM AUTHOR]

Graphene–WO 3 composites mixed with different amounts of graphene (0, 0.1, 0.5, 1 and 3 wt%) were prepared by hydrothermal method at 180 °C for 24 h. The as-prepared graphite oxide, graphene and graphene–WO 3 composites were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectra (FT-IR) and Raman spectroscopy, respectively. The effect of the amount of graphene in the composites on the gas-sensing responses and the gas-sensing selectivity of the materials was investigated. The experimental results revealed that the sensor based on 0.1 wt% graphene–WO 3 composite exhibited high response and good selectivity to acetaldehyde vapor at 100 °C, the optimum operating temperature of this sensor to 1000 ppm acetaldehyde vapor decreased from 180 °C to 100 °C comparing with that of pure WO 3 . The response time and the recovery time for 100 ppm acetaldehyde vapor were 250 s and 225 s, respectively. [ABSTRACT FROM AUTHOR]

Abstract: In this work, ceramic–polymer composites were fabricated from barium strontium titanate powder (BST) and polypropylene-graft-poly(styrene-stat-divinylbenzene) (ER) using a twin-screw extruder. The compounding process was characterized by rheological measurements. The effects of volume loading of BST on dielectric and mechanical properties were investigated. The dielectric properties were measured as a function of frequency and BST loading. For example, the relative permittivity and loss tangent (tan δ) of the BST–ER composites at 1GHz were gradually increased from 2.4 and 0.0001 to 28.5 and 0.0085, respectively, as the loading was increased from 0 to 50.5vol.%. Stearic acid (StA) was used as a surface-modifier of the BST. With an approximate surface coverage of 83%, an improvement in processability and a slight increase of the permittivity was observed, while tan δ remained low. The excellent dielectric characteristics of these composites, with high permittivity and low tan δ, make them attractive novel electronic materials for high frequency applications. [Copyright &y& Elsevier]

Abstract: Ferroelectric ceramic–polymer composites provide flexible self-sustaining thin layers with unique electrical and mechanical properties, and thus a novel way to fabricate RF devices. In this work, a composite made of ferroelectric ceramic (barium strontium titanate, BST) and thermoplastic polymer (polyphenylene sulfide, PPS) was studied with various BST loadings up to 70wt.%. The microstructures exhibited uniform distribution of ceramic particles in the polymer matrix. RF measurements showed that the relative permittivity and loss tangent of the composites gradually increase with increasing BST loading. At 1GHz a composite with 70wt.% BST loading had relative permittivity and a loss tangent of 13.5 and 0.0025, respectively. [Copyright &y& Elsevier]

In this work, a room temperature liquid metal alloy (Galinstan) and tungsten diselenide (WSe 2) composite anode (LM x @WSe 2) were synthesized utilizing a one-step hydrothermal method. Through a comprehensive characterization process, including XRD, SEM, HRTEM, Raman spectroscopy, XPS, and BET, the structural and morphological properties of the synthesized composites were extensively explored. The liquid metal alloy was observed to combine effectively with WSe 2 via electrostatic adsorption, coordination, and additional bonding methods. Furthermore, it displayed high fluidity, deformability, and chemical stability. Consequently, the alloy promoted the repair of cracked surface areas in the electrode material and reduced internal oxidation-reduction reactions, leading to improved electrochemical performance during repeated lithium-ion insertion and extraction cycles. After 500 cycles at a current density of 1 A g−1, this composite electrode retained a capacity of 224.5 mAh g−1. Impressively, at a low temperature of − 10 °C, it maintained a capacity of 290 mAh g−1 after 50 cycles at a current density of 0.2 A g−1. Our research may open avenues for addressing mechanical difficulties experienced in flexible electronic devices and self-healing electronic circuits exposed to chemical reaction processes. • Liquid metal alloy (Galinstan) /WSe 2 composite anode was synthesized for LIBs. • Successful combination of liquid metal alloy and WSe 2 via various bonding methods. • High fluidity, deformability, and chemical stability observed in the alloy. • Electrochemical performance with superior capacity retention & low-temp. stability. [ABSTRACT FROM AUTHOR]

This paper highlights the synthesis of a one-dimensional (1D) hierarchical material mesosilica/palygorskite (Pal) composite and evaluates its adsorption performance for anionic dye methyl orange (MO) in comparison with Pal and Mobile crystalline material-41 (MCM-41). The Mesosilica/Pal composite is consisted of mesosilica coated Pal nanorods and prepared through a dual template approach using cetyltrimethyl ammonium bromide (CTAB) and Pal as soft and hard templates, respectively. The composition and structure of the resultant material was characterized by a scanning electron microscope (SEM), transmissionelectron microscopy (TEM), N2 adsorption-desorption analysis, small-angle X-Ray powder diffraction (XRD), and zeta potential measurement. Adsorption experiments were carried out with different absorbents at different contact times and pH levels. Compared with Pal and MCM-41, the mesosilica/Pal composite exhibited the best efficiency for MO adsorption. Its adsorption ratio is as high as 70.4%. Its adsorption equilibrium time is as short as 30 min. Results testify that the MO retention is promoted for the micro-mesoporous hierarchical structure and positive surface charge electrostatic interactions of the mesosilica/Pal composite. The regenerability of the mesosilica/Pal composite absorbent was also assessed. 1D morphology makes it facile to separate from aqueous solutions. It can be effortlessly recovered and reused for up to nine cycles. Keywords: adsorption; mesosilica; methyl orange [ABSTRACT FROM AUTHOR]

[Display omitted] • The controllable synthesis of AgNWs@WSe 2 via solvothermal method was achieved. • The as-fabricated AgNWs@WSe 2 promotes the entire electrochemical process. • Ion diffusion coefficient of WSe 2 powder and AgNWs@WSe 2 were obtained using GITT. • Finite element simulations reveals rapid electron/ion diffusion kinetics. A nanocomposite (AgNWs@WSe 2) consisting of tungsten diselenide (WSe 2) nanosheets decorated with silver nanowires (AgNWs) was synthesized by a simple solvothermal method. In order to investigate its lithium-ion storage performance, AgNWs act as an effective backbone for the in-situ growth of WSe 2 on its surface. Compared with pure tungsten diselenide electrode material, this composite material has more excellent multiplicative performance and long cycle stability(348.7 mAh g-1 at 1 A g-1 after 500 cycles). Additional results combined with COMSOL simulations further demonstrate the superior lithium performance of the composite electrode, mainly due to the typical one-dimensional AgNWs provide direct channels for electron transfer, slowing down the volume expansion during lithium ion embedding/detachment, and inhibit mechanical degradation, thus enabling longer cycling life. [ABSTRACT FROM AUTHOR]

As an organic-inorganic composite material, sticky rice slurry-lime mortar (SLM) is being used more and more as a repair material in the preservation of cultural heritage. Taking advantage of environmental scanning electron microscopy and the digital-image correlation technique, the microdeformation and damage mechanisms of SLM subject to wetting/drying are investigated in this study. Three wetting-drying cycles between 20 and 98 % relative humidity (RH) are carried out with different hydric loading rates (i.e., 10 % RH/min, 40 % RH/min, instantaneous RH change). Micro-observation and full-field strain measurement are performed on a domain of size 400 $$\times $$ 345 $$\upmu $$ m $$^2$$ . The results reveal that SLM subject to wetting-drying exhibits a heterogeneous strain field that correlates well with the heterogeneous microstructure of the SLM. In the first cycle, the global swelling strain is 0.25 % when RH increases from 20 to 98 %; when re-drying back to 20 % RH, we found an irreversible strain 0.04 %. The latter is demonstrated to arise from the propagation of pre-existing microcracks during the drying path. However, in the following two wetting-drying cycles, the microcracks become stable, and the irreversible strain changes slightly. [ABSTRACT FROM AUTHOR]

Abstract: Titania–alumina supports were prepared successfully using the ultrasound-assisted precipitation method. The resulting supports were characterized by fourier transform infrared analysis (FTIR), scanning electron microscope (SEM), X-ray diffraction (XRD) and N2 physisorption. The effects of precipitants, washing method and the addition of surfactant CTAB were studied. The supports prepared with NH4HCO3 showed better textural properties compared with that with NH3·H2O, which was attributed to the low NH4 + release rate of NH4HCO3. TiO2–Al2O3 support with S BET =283m2/g, V p =2.34mL/g and D p =33.0nm was obtained with this modified precipitation method. [ABSTRACT FROM AUTHOR]