Unique Network Structure Research Articles

The impact of social media discourse on financial performance of e-commerce companies listed on Borsa Istanbul

This research investigates how changes in public discourse on social media (particularly Twitter, now X) influence financial performance of companies listed on the e-commerce XTCRT index of Borsa Istanbul amid the COVID-19 pandemic. Utilising a unique 4-layer network structure, the study integrates daily closing prices, highest and lowest values, and trading volume data of these companies with Twitter discussions on six categories: culture, economy, health, politics, technology, world affairs. By using advanced computational methods such as multilayer network analysis, long short-term memory architecture, nonlinear autoregressive distributed lag analysis, we find a high responsiveness of the e-commerce index to social media content, particularly in discussions related to health, technology, world affairs. The study underscores that social media discussions significantly shape index composition, resulting in noticeable shifts in market dynamics, including fluctuations in stock prices, trading volumes, and market sentiment. Our study advocates for a more advanced approach to market analysis that incorporates the dynamics of online public discussions.

The network structure and properties of a unique mining solid waste-based glass-ceramics

To alleviate the environmental pollution caused by the stockpile of mining-based, such as coal-based solid waste, mining solid waste-based CaO-MgO-Al2O3-SiO2 (CMAS) glass-ceramics with a diopside phase as the main crystalline phase was developed by one-step sintering method, and the effect of different solid waste content on the network structure and properties were investigated. The results show that, with the diversification of solid waste content, the crystallization temperature (Tp), the amount of Fe3+ concentration, and diopside crystalline, the main structure of glass Q2 changed also. Accordingly, significant changes have occurred in properties such as the bending strength, Vickers hardness, and density. Optimizing the raw material ratio, crystallization mechanism, a mining solid waste-based glass-ceramic with unique network structure is well developed and the bending strength, Vickers hardness, fracture toughness, and density reaches maximum values of 175.19 MPa, 10.47 GPa, 2.03 MPa⋅m1/2, and 3.00 g/cm3, respectively. The findings contribute significantly to the development of durable and reliable materials for the utilization of mining solid waste resources.

Enhanced sensitivity and broadband response in porous triple periodic minimal surface piezoresistive sensors for telemedicine applications

Wearable pressure sensors with outstanding performance have garnered significant attention in fields such as telemedicine. However, the development of sensors that achieve both adjustable high sensitivity and a wide response range remains a formidable challenge. To address these issues, we propose the development of a flexible piezoresistive sensor featuring simultaneous macro- and microstructures. This is achieved by constructing a complex macro-topological skeleton using Fused Deposition Molding (FDM) technology and integrating supercritical carbon dioxide (ScCO2) foaming technology for microscopic pore creation. The unique conductive network structure, coupled with the Triple Periodic Minimal Surface (TPMS) metamaterial framework and microscopic pore architecture, endows the piezoresistive sensors with exceptional sensing performance, including high sensitivity (12.13 MPa−1), a broad response range (exceeding 30 MPa), and long-term fatigue resistance (over 26,000 s cycles). In addition, the sensors are shielded from electromagnetic interference, with a maximum EMI shielding effectiveness of 53.2 dB for the TMFM with a thickness of 2.3 mm. The effects of varying porosities and foaming pressures on sensitivity were analyzed using finite element simulations. Owing to these remarkable features, multiple foot movement recognition was successfully demonstrated with volunteer participants by assembling sensing unit array modules. Based on this, an intelligent fall warning recognition system is developed using machine learning. This system accurately distinguishes four types of activity behaviors—standing, walking, spraining foot, and falling—with accuracy rates of 98.9 %, 97.1 %, 98.9 %, and 95.1 %, respectively. The system automatically generates an alarm pattern for detected fall behaviors. These findings suggest that the combination of TPMS skeleton and micropores structure offers a promising strategy for developing sensors with adjustable sensitivity and wide detection range for wearable devices. This technology holds significant potential for applications in telemedicine assistance, particularly for the elderly and other vulnerable populations.

A novel negative thermal expansion ceramic network interlayer for releasing high residual stress of Cf/SiC heterogeneous brazed joint

Negative thermal expansion (NTE) ceramics have been widely concerned in adjusting the coefficient of thermal expansion (CTE) to release the high residual stress of heterogeneous joint. However, one major problem that needs to be solved is the agglomeration problem caused by excessive ceramic particles addition. In this work, a novel NTE ceramic Sc2W3O12 network interlayer is prepared by the polyurethane template method. The Sc2W3O12 network interlayer with a single NTE phase presents a three-dimensional network structure. The NTE Sc2W3O12 ceramic is uniformly distributed in brazing seam without agglomeration with the help of unique network structure. The active Ti elements play an important role in the interface bonding, reacted with Sc2W3O12 network interlayer and Cf/SiC composites to form Cu3Ti3O and TiC/Ti5Si3 reaction layer, respectively. After introducing Sc2W3O12 network interlayer, the CTE of the composite filler is reduced from 16.6 × 10−6 K−1 to 11.9 × 10−6 K−1, a decrease of 29 %. The highest shear strength of the Cf/SiC heterogeneous joint is reached 130 MPa, which is 5.4 times than that without Sc2W3O12 network interlayer.

Aerogel‐Driven Interface Rapid Self‐Gelation Enables Highly Stable Zn Anode

AbstractThe practical application of Zn metal anodes is currently hindered by uncontrolled dendritic growth and water‐induced parasitic reactions that are closely related to the solvation structure and interfacial transport kinetics of Zn2+. Herein, a facile interface self‐gelation strategy is proposed to stabilize Zn anode by introducing ‐OH‐rich silica aerogel (HSA) on Zn anode surface. The unique interconnected network structure and strong hydrophilia of HSA made the aqueous electrolyte near Zn anode gel rapidly and spontaneously, resulting in the formation of a water‐poor gel interface layer. The interface layer can effectively accelerate the desolvation process and reduce water molecule activity near anode surface through hydrogen bonding interaction, thus achieving rapid Zn migration kinetics and alleviating side reactions. In addition, the well‐defined aerogel nanochannels can provide a fast Zn2+ migration path and homogenize Zn2+ flux, enabling rapid and uniform Zn deposition. As a result, the HSA‐modified Zn (HSA@Zn) anode exhibits excellent long‐term cycling stability (over 6000 h at 4 mA cm−2), and the feasibility for practical application of this HSA@Zn anode is further demonstrate in full cells. The aerogel‐driven interface self‐gelation strategy propose in this work provides new insights into the design of advanced Zn anode for aqueous zinc‐ion batteries.

Amine-modified SiO2 aerogel for efficient adsorption of low-pressure CO2: Response surface methodology optimization and adsorption mechanism

Amine-modified SiO2 aerogel (AMSA) has shown tremendous potential in CO2 capture due to its unique three-dimensional network structure and excellent stability. However, it still faces many challenges in the preparation optimization, adsorption enhancement at low CO2 partial pressure, and mechanism elucidation. Hence, in this paper, the response surface methodology is employed for the first time and the optimal preparation conditions for AMSA are determined. A regression model is successfully established to accurately predict the CO2 adsorption capacity of AMSA under different synthesis conditions (with a relative error of only 0.98 %). Additionally, the AMSA prepared at optimal conditions exhibits high CO2 adsorption capacity of 2.11 mmol/g and excellent stability (only decreased by 1.44 % after 8 cycles) at 10 % CO2 partial pressure, indicating enormous application potential. Notably, the CO2 adsorption mechanism by AMSA at different temperatures and partial pressures are revealed in detail through fitting with the Freundlich isotherm and the double-exponential model, as well as thermodynamic parameter calculations. Firstly, the CO2 adsorption behavior belongs to the multi-layer adsorption behavior with uneven energy of active sites. Secondly, the CO2 adsorption capacity and rate are jointly controlled by molecular motion and chemical reaction equilibrium, diffusion and chemical reaction steps, respectively. Finally, the adsorption process is exothermic and spontaneous, and the level of disorder decreases at the gas-solid interface. This study not only achieves efficient adsorption of low-pressure CO2, but also deepens the understanding of gas-solid interface adsorption mechanisms, providing scientific basis and technological support for the development of novel efficient AMSA adsorbent materials.

High toughness, flexible and thermally conductive fluorine rubber composite films reinforced by hexagonal boron nitride flakes for thermal management

The rapid advancement of electronic information technology has generated a substantial demand for polymer-based thermal management materials. In order to address the challenges of heat dissipation and avoid signal interference, it is essential to develop polymer-based thermal management materials with both high thermal conductivity and low dielectric properties. Herein, hexagonal boron nitride flakes (h-BNFs) with a high aspect ratio and some hydroxyl groups were prepared using the high pressure homogenization technique. Subsequently, h-BNF/fluorine rubber (h-BNF/FKM) composite films were fabricated through a simple and scalable blade coating method. During the blade coating process, most of the h-BNFs can align with their (002) crystal planes paralleling to the horizontal direction. In addition, the rest of the h-BNFs will randomly distribute and overlap with each other, combining with the horizontally aligned h-BNFs to form a distinctive three-dimensional packing network. This unique network structure enables the h-BNF/FKM composite films to have thermal conductivities of up to 0.44 W/(m·K). Moreover, the introduction of h-BNFs can effectively reduce the dielectric constants and dielectric losses of FKM films. More importantly, the h-BNF/FKM composite films also exhibit outstanding mechanical toughness, excellent flexibility, good adhesion and improved flame-retardancy, providing promising applications in the electronic device thermal management.

A facile way to fabricate a thrombin immobilized composite sponge with dual hemostatic effects for acute hemorrhage control

Uncontrolled bleeding and excessive blood loss stand as the leading causes of death in complex surgeries, civilian traumas, and military operations. Sponges have been used for developing efficiency hemostats, but most commonly used hemostatic sponges possess only one single coagulation mechanism or lack inherent blood clotting ability. Herein, we proposed simple yet innovative approaches for creating novel hemostatic composite sponges with dual hemostatic effects. Bacterial cellulose (BC) was first introduced into polyvinyl alcohol (PVA) matrix to develop a BC/PVA (CP) sponge featuring a unique cellulose-embedded porous network structure and desirable properties. Subsequently, thrombin was immobilized on CP through an easy method that combines physical adsorption and covalent binding to fabricate thrombin-carrying CP (TCP) composite sponges. The resulting composites boasted a highly porous structure, outstanding liquid-absorption capacity, low hemolysis rate, and superior biocompatibility. In vitro clotting tests revealed that TCP displayed potent coagulation capabilities, a rapid blood absorption rate, and the ability to stimulate and activate blood components along with the coagulation cascade. In vivo hemostatic assessments further confirmed that TCP offered high hemostatic efficiency and multifaceted hemostatic effects, making it suitable for the management of acute and severe bleeding.

In-Situ Sulfuration of CoAl Metal-Organic Framework for Enhanced Supercapacitor Properties.

Designing efficient electrode materials is necessary for supercapacitors but remains highly challenging. Herein, cobalt sulfide with crystalline/amorphous heterophase (denoted as Co(Al)S) derived from an Al metal-organic framework was constructed by ion exchange/acid etching and subsequent sulfidation strategy. It was found that rational sulfidation by adjusting the sulfur source concentration to a suitable level was favorable to form a 3D nanosheet-interconnected network architecture with a large specific surface area, which promoted ion/electron transport and charge separation. Benefiting from the features of the unique network structure and heterophase accompanied by aluminum, nitrogen and carbon coordinated in amorphous phase, the optimal Co(Al)S(10) exhibited a high specific capacity (1791.8 C g-1 at 1 A g-1), an outstanding rate capability and an excellent cycling stability. Furthermore, the as-assembled Co(Al)S//AC device afforded an energy density of 72.3 Wh kg-1 at a power density of 750 W kg-1, verifying that the Co(Al)S was a promising material for energy storage devices. The developed scheme is expected to promote the application of MOF-derived electrode materials in electrochemical energy storage and conversion fields.

SAR images change detection using proposed lamina attention-based noise-resistant UNet advance network (LANRUNet++)

In the past few years, change detection techniques using Convolutional Neural Networks (CNNs) and conventional methods have garnered considerable attention in satellite image analysis. However, both categories of existing approaches have their respective shortcomings. For instance, methods based on CNNs tend to overlook the interactions amongst multilayer convolutions, while traditional methods may contain errors in the initial classification stage that limit the optimization of network. To address these limitations, we propose a new attentionbased, noise-resistant advanced UNet model named as Lamina Attention-Based Noise-Resistant UNet Advance Network (LANRUNet++)for detecting changes in satellite imagery. UNet++ is a unique neural network structure composed of an encoder and decoder, that are linked by a sequence of dense convolutional blocks nested within each other. A core principle underlying the proposed LANRUNet++ is to effectively bridge the semantic disparity between the encoder and decoder feature maps prior to their fusion. We present a lamina attention mechanism within UNet++, which dynamically assigns weights to features extracted from various convolutional layers. This facilitates improved incorporation of spatial context information. Moreover, we added a loss function that is robust to noise and can effectively minimize the influence of inaccurate annotations. As a result, our model becomes less susceptible to errors in initial classification outcomes. Furthermore, we added a Pixel to Density Ratio Parameter that further reduces noisy labels, improving the robustness of the model.We conducted a comprehensive performance assessment of LANRUNet++ on SAR images and conducted a comparative analysis against a range of cutting-edge techniques currently available. The results of our experiments demonstrate that our proposed approach surpasses other existing methods in its ability to detect changes, achieving a higher level of accuracy with various metrics.

Flexible high electrochemical active hydrogel for wearable sensors and supercapacitor electrolytes

With the rapid advancement of flexible, portable devices, hydrogel electrolytes have gained considerable attention as potential replacements for conventional liquid electrolytes. A hydrogel electrolyte was synthesised by cross-linking acrylic acid (AA), acrylamide (AM), carboxymethyl cellulose (CMC), and zinc sulphate (ZnSO4). The formation of hydrogen bonds and chelate interactions between the P(AA-co-AM) polymer, CMC, and ZnSO4 created a robust network, enhancing the mechanical properties of the hydrogel electrolytes. Notably, the hydrogel electrolyte containing 0.6 % CMC demonstrated superior mechanical strength (compression strength of 1.22 MPa, tensile stress of 230 kPa, tensile strain of 424 %, adhesion strength of 1.98 MPa on wood). Additionally, the CMC/P(AA-co-AM) hydrogels exhibited commendable electrical performance (38 mS/cm) and a high gauge factor (2.9), enabling the precise detection of physiological activity signals through resistance measurements. The unique network structure of the hydrogel electrolyte also ensured a stable bonding interface between the electrode and the electrolyte. After 2000 charge–discharge cycles, the supercapacitor maintained good capacitance characteristics, with a capacitance retention rate of 71.21 % and a stable Coulombic efficiency of 98.85 %, demonstrating excellent cyclic stability. This study introduces a novel methodology for fabricating multifunctional all-solid-state supercapacitors and suggests that the hydrogel can significantly advance the development of wearable energy storage devices.

Al-Based MOF-Derived Amorphous/Crystalline Heterophase Cobalt Sulfides as High-Performance Supercapacitor Materials.

Transition metal sulfides (TMSs) are promising electrode materials due to their high theoretical specific capacitance, but sluggish charge transfer kinetics and an insufficient number of active sites hamper their applications in supercapacitors. In this work, a self-sacrificial template strategy was employed to construct Al-based MOF-derived metal sulfides with an amorphous/crystalline (a/c) heterophase, in which aluminum, nitrogen, and carbon species were evenly coordinated in the amorphous phase. The metal sulfides a/c-Co(Al)S-1 and a/c-Co(Al)S-2, originating from the CAU-1 and CoAl-MOF on NF as self-sacrificial templates, were investigated as electrode materials, respectively, in which the a/c-Co(Al)S-1 showed a more excellent electrochemical performance. Through acid etching CAU-1 using Co(NO3)2 followed by sulfuration, the a/c-Co(Al)S-1 with a unique 3D network structure was constructed, whose unique architecture expanded the interfacial contact with the electrolyte and provided vast active sites, accelerating the charge transportation and ion diffusion. Notably, the a/c-Co(Al)S-1 displayed a high specific charge of 1791.8 C g-1 at 1 A g-1, satisfactory cycle stability, and good rate capability. The corresponding assembled a/c-Co(Al)S-1//AC device delivered a high energy density of 77.1 Wh kg-1 at 800 W kg-1 and good durability (87.4% capacitance retention over 10 000 cycles).

Achieving superior compressive strength-ductility synergy in a novel ODS-CrFeNi/AlCrFeNi heterostructured high-entropy composite

A novel high-entropy heterostructured composite (ODS-CrFeNi/AlCrFeNi) was fabricated by powder metallurgy method. The microstructure and mechanical properties of the composites with various sintering temperatures (950 °C to 1100 °C) and various addition amounts (0% to 20%) of FCC-structured reinforcing phase (ODS-CrFeNi) were investigated. The results revealed a reduction in porosity and an increase in relative density, reaching up to 99% with increasing sintering temperature. The optimal sintering temperature is 1100 °C. In the composites with the addition of 5% and 10% ODS-CrFeNi reinforced phases, spinodal decomposition (SD), forming BCC and B2 phases, takes place both in the matrix and in the reinforcing phase. As the reinforcing phase content is increased to 15% and 20%, SD occurs exclusively in the matrix while is suppressed in the reinforcing phase. The reinforcing phase consists of hard BCC structured Cr rich phases and soft FCC-structured FeNi phases, forming a gradient network structure. The composite with 15% reinforcing phase exhibits high hardness of 841 HV and compressive yield strength, ultimate strength and strain of 6960 MPa, 7690 MPa and 15.5%, respectively, which are 2.5, 2.7 and 1.9 times higher than those of the reference alloys (without reinforcing phase). The excellent strength-ductility synergy originates from the unique gradient network structure formed in the reinforcing phase, i.e. complex heterogeneous structure, which results in hetero-deformation induced (HDI) strengthening for higher strength and HDI strain hardening for higher ductility.

Preparation of cellulose derived carbon/reduced graphene oxide composite aerogels for broadband and efficient microwave dissipation

The development of cellulose derived carbon-based composite aerogels with light weight, broad bandwidth and strong absorption remains a challenging task. In this work, the cellulose derived carbon/reduced graphene oxide composite aerogels were prepared by a two-stage process of chemical crosslinking and high-temperature carbonization. The results revealed that the as-fabricated binary composite aerogels had a unique lightweight characteristic and three-dimensional porous network structure, which was chemically crosslinked by epichlorohydrin. Furthermore, the weight concentration of graphene oxide (GO) had a notable influence on the electromagnetic parameters and microwave absorption properties of the composite aerogels. The obtained binary composite aerogel possessed the optimal microwave dissipation capability when the concentration of GO was 1.5 mg/mL. Remarkably, the minimum reflection loss reached −50.42 dB at a thickness of 2.47 mm and a filling ratio of 17.5 wt%. Concurrently, the composite aerogel with a comparable thickness of 2.73 mm showed a wide effective absorption bandwidth of 7.28 GHz, spanning the total Ku-band and extending into a portion of the X-band. The radar cross section contribution of binary composite aerogels in the far-field was also simulated by computer simulation technique. In addition, the potential microwave attenuation mechanism was proposed. It was believed that the results of this paper would offer a reference for the preparation of cellulose derived carbon-based composite aerogels as efficient and broadband microwave absorbers.

Stable, Scalable, and Free-Standing Perovskite Quantum Dots Composite Reinforced by Cellulose Fibers.

Perovskite quantum dots (PQDs) have attracted emerging attention as fluorescent and light-absorbing materials for next-generation optoelectronics due to their outstanding properties and cost-efficiency. However, PQD thin film suffers significant instability due to structure and material failures, which hinders their application in flexible and reliable PQD-based advanced wearable devices. Herein, we use commercial cellulose fiber-based filter paper as a substrate to synthesize PQDs in situ and fabricate PQD-paper free-standing flexible composite film. The abundant hydroxy capping ligands of cellulose fibers and the unique dense network structure of the filter paper can facilitate confined crystallization, forming strong interactions between the PQDs and substrate, the unpackaged PQD composite film showed extraordinary stability (>30 days) in the air with high humidity (90%). Meanwhile, the strong interaction between PQDs and paper enables an ultrasimple drop-cast synthesis process with excellent process tolerance, making it customizable and easy to scale up (10 cm in diameter). Due to the uniformly dispersed PQDs on cellulose fibers of the substrate, the composite demonstrates impressive photo-responsive properties. Photodetector (PD) arrays were designed on free-standing PQD paper and flexible graphitic electrodes, and circuits were fabricated by drawing. The PD arrays can work as optical and electrical dual-mode image sensors with incredible bending robustness, enduring up to 100,000 cycles at 180°.

Design of flexible micro-porous fiber with double conductive network synergy for high-performance strain sensor

Flexible wearable strain sensor is a vital part of intelligent wearable systems due to their broad applications in human–machine interaction and smart clothes. Flexible strain sensor fabricated via conventional blending conductive polymer composites has some drawbacks, for example, low sensitivity, large hysteresis, and “shoulder-peak” phenomenon, which limit their practical applications greatly. Herein, we prepared a fiber-shaped strain sensor with a micro-porous, three-layer structure together with a dual conductive network based on reduced graphene oxide (rGO) and multi-walled carbon nanotubes (MWCNTs). The strain sensor demonstrates excellent response behaviors, including splendid stretchability (686 %), wide detection range (120 %), high sensitivity (gauge factor = 300), fast response time (300 ms) and excellent durability (over 9000 cycles). The unique dual conductive network structure endows the strain sensor with remarkable recoverability and reproducibility. The resistance of the strain sensor can recover to nearly initial conditions after the releasing process, exhibiting lower hysteresis. The “shoulder-peak” phenomenon has also been weakened based on the microstructure and conductive network design. Based on the high sensitivity and excellent response behavior, the fiber-shaped strain sensor performs real-time monitoring of breathing, finger bending, walking, and other human motions, providing a good candidate for its application in intelligent wearable devices.

Portable electrochemical sensor for adrenaline detection using CoNi-MOF-based CS-PAM hydrogel

The development of a portable smartphone-based electrochemical sensor for analyzing adrenaline levels in real samples can make a great contribution to the research community worldwide. In order to achieve this goal, the key challenge is to build sensing interfaces with excellent electrocatalytic properties. In this work, microspherical bimetallic metal–organic frameworks (CoNi-MOF) consisting of nanoclusters were first synthesized using a hydrothermal method. On this basis, the catalytic activity of pure chitosan-polyacrylamide hydrogel (CS-PAM) was modulated by adding different amounts of CoNi-MOF during the in-situ synthesis of CS-PAM. Finally, a portable electrochemical detection system based on CS-PAM was established for the detection of adrenaline. A series of resulting composite hydrogels with a large specific surface area, abundant active sites, and unique network structure facilitate the enrichment and catalysis of adrenaline molecules. Under optimal conditions, the analytical platform constructed by using CoNi-MOF-based CS-PAM has the advantages of a wide detection range (0.5–10 and 10–2500 μM), a low detection limit (0.167 μM), and high sensitivity (0.182 and 0.133 μA·μM·cm−2). In addition, the sensor maintains selective detection of the target in the presence of many different types of interferences, and the current response is not significantly reduced even after 60 cycles of testing. We strongly believe that the designed smart portable sensing can realize the accurate determination of adrenaline in complex systems, and this study can provide new ideas for the research of MOFs-based hydrogels in electrochemical analysis.

Theoretical study on the effective thermal conductivity of silica aerogels based on a cross-aligned and cubic pore model

Abstract Aerogel nanoporous materials possess high porosity, high specific surface area, and extremely low density due to their unique nanoscale network structure. Moreover, their effective thermal conductivity is very l1ow, making them a new type of lightweight and highly efficient nanoscale super-insulating material. However, predicting their effective thermal conductivity is challenging due to their uneven pore size distribution. To investigate the internal heat transfer mechanism of aerogel nanoporous materials, this study constructed cross-aligned and cubic pore model (CACPM) based on the actual pore arrangement of SiO2 aerogel. Based on the established cross-aligned and cubic pore model (CACPM), the effective thermal conductivity expression for aerogel was derived by simultaneously considering gas-phase heat conduction, solid-phase heat conduction, and radiative heat transfer. The derived expression was then compared with available experimental data and the Wei structure model. The results indicate that, according to the model established in this study for the derived thermal conductivity formula of silica aerogel, for powdery silica aerogel under the conditions of T=298K, a 2=0.85, D 1=90μm, ρ=128kg/m3, within the pressure range of 0-105Pa, the average deviation between the calculated values and experimental values is 10.51%. In the pressure range of 103-104Pa, the deviation between calculated values and experimental values is within 4%. Under these conditions, the model has certain reference value in engineering verification. This study also makes a certain contribution to the research of aerogel thermal conductivity heat transfer model and calculation formula.

Metal-organic framework-based aptasensor utilizing a novel electrochemiluminescence system for detecting acetamiprid residues in vegetables

The work was based on N-(4-Aminobutyl)-N-ethylisoluminol (ABEI)-functionalized Fe-MIL-101 and gold nanoparticles (AuNPs) as sensing materials, and an electrochemiluminescence (ECL) aptasensor was constructed for detecting acetamiprid. As a metal-organic framework (MOF) material, Fe-MIL-101, was renowned for its unique three-dimensional network structure and efficient catalytic capability. ABEI, a common ECL reagent, was widely applied. ABEI was introduced into the Fe-MIL-101 structure as a luminescence functionalization reagent to form Fe-MIL-101@ABEI. This approach avoided limitations on the loading capacity of luminescent reagents imposed by modification and encapsulation methods. With character of excellent catalytic activity and ease of bioconjugation, AuNPs offered significant advantages in biosensing. Leveraging the reductive properties of ABEI, AuNPs were reduced around Fe-MIL-101@ABEI, resulting in the modified luminescent functionalized material denoted as Fe-MIL-101@ABEI@AuNPs. An aptamer was employed as a recognition element and was modified accordingly. The aptamer was immobilized on Fe-MIL-101@ABEI@AuNPs through gold-sulfur (Au–S) bonds. After capturing acetamiprid, the aptamer induced a decrease in the ECL signal intensity within the ABEI-hydrogen peroxide (H2O2) system, enabling the quantitative detection of acetamiprid. The aptasensor displayed remarkable stability and repeatability, featured a detection range of 1×10−3-1×102 nM, and had a limit of detection (LOD) of 0.3 pM (S/N=3), which underscored its substantial practical application potential.

A three-dimensional BaFe11.6(ZrSm)0.2O19/rGO composite aerogel with superior microwave absorption properties

The combination of dielectric and magnetic materials can significantly improve microwave absorption properties. In this work, we introduce a novel Zr–Sm doped barium ferrite BaFe11.6(ZrSm)0.2O19, which is compounded with rGO aerogel and presents superior microwave absorption properties. The results show that the BaFe11.6(ZrSm)0.2O19/rGO composite aerogel exhibits a unique three-dimensional porous network structure which enhances the reflection and scattering of electromagnetic waves. Meanwhile, the addition of BaFe11.6(ZrSm)0.2O19 abounds the folds and defects on the surface of rGO sheet layer, generating a large amount of polarisation and relaxation. In addition, with the increase of BaFe11.6(ZrSm)0.2O19 content, the permeability gradually increases, while the dielectric constant gradually decreases. At a certain content, both of them can be well balanced to obtain high attenuation constants and great impedance matching, which regulates the wave-absorbing properties of the material. The minimum reflection loss (RLmin) of BaFe11.6(ZrSm)0.2O19/rGO composite aerogel can reach −53.17 dB at a matching thickness of 2.9 mm, and the absorption bandwidth reaches 7.04 GHz, which has been improved by 40% than pure BaFe11.6(ZrSm)0.2O19. Therefore, it is expected to be a candidate for lightweight, thin, high loss, large bandwidth microwave absorbing materials.