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The rapid development of miniaturized, high-frequency, and highly integrated microelectronic devices has brought about critical issues in electromagnetic compatibility and thermal management. In recent years, there has been significant interest in lightweight polymer-based composites that offer both electromagnetic interference (EMI) shielding and thermal conductivity. One promising approach involves constructing three-dimensional (3D) interconnection networks using functional fillers in the polymer matrix. These networks have been proven effective in enhancing the thermal and electrical conductivity of the composites. This mini-review focuses on the preparation and properties of 3D network-reinforced polymer composites, specifically those incorporating metal, carbon, ceramic, and hybrid networks. By comparing the effects of different filler types and distribution on the composite materials, the advantages of 3D interconnected conductive networks in polymer composites are highlighted. Additionally, this review addresses the challenges faced in the field of multifunctional thermal management and electromagnetic protection materials and provides insights into future development trends and application prospects of 3D structured composites. [ABSTRACT FROM AUTHOR]

The success of next-generation Internet of Things (IoT) applications could be boosted with state-of-the-art communication technologies, including the operation of millimeter-wave (mmWave) bands and the implementation of three-dimensional (3D) networks. With some access points (APs) mounted on unmanned aerial vehicles (UAVs), the probability of line-of-sight (LoS) connectivity to IoT nodes could be augmented to address the high path loss at mmWave bands. Nevertheless, system optimization is essential to maintaining reliable communication in 3D IoT networks, particularly in dense urban areas with elevated buildings. This research adopts the implementation of a geometry-based stochastic channel model. The model customizes the standard clustered delay line (CDL) channel profile based on the environmental geometry of the site to obtain realistic performance and optimize system design. Simulation validation is conducted based on the actual maps of highly dense urban areas to demonstrate that the proposed approach is comprehensive. The results reveal that the use of standard channel models in the analysis introduces errors in the channel quality indicator (CQI) that can exceed 50% due to the effect of the environmental geometry on the channel profile. The results also quantify accuracy improvements in the wireless channel and network performance in terms of the CQI and downlink (DL) throughput. [ABSTRACT FROM AUTHOR]

Metal oxide semiconductors (MOSs) hold great promise for electronic devices such as gas sensors. The utilization of ZnO as a conductometric gas sensor material can be traced back to its early stages; however, its application has primarily been limited to high-temperature environments. A gas sensor based on highly porous and interconnected 3D networks of ZnO tetrapod (ZnO-T) micro-nano structures was fabricated via an easy chemical vapor deposition (CVD) method. Homemade instruments were utilized to evaluate the gas-sensing of the sample at room temperature. It exhibited good gas-sensing at room temperature, particularly with a response of up to 338.80% toward 1600 ppm ethanol, while also demonstrating remarkable repeatability, stability, and selectivity. Moreover, the unique gas-sensing properties of ZnO-T at room temperature can be reasonably explained by considering the effect of van der Waals forces in physical adsorption and the synergistic effect of carrier concentration and mobility. The aforementioned statement presents an opportunity for the advancement of gas sensors utilizing ZnO at room temperature. [ABSTRACT FROM AUTHOR]

This work aims to address the heat accumulation issue in electronic components during high‐frequency operation through the preparation of novel thermally conductive composites. First, polydopamine (PDA) and in‐situ growth of silver (Ag) nanoparticles are applied for the surface modification of graphene oxide (GO) and carbon nanotube (CNT) to prepare pGO@Ag and pCNT@Ag hybrid filler, respectively. Then, nitrile butadiene rubber (NBR) is chosen as the polymeric matrix and simultaneously incorporated with both pGO@Ag and pCNT@Ag to prepare polymeric composites with excellent thermal conductivity (TC) and dielectric constant (ɛr). Due to the construction of 3D heat conduction networks by utilizing 2D pGO@Ag and 1D pCNT@Ag, the fabricated NBR composites achieved the maximum TC of 1.0112 W/(mK), which is 636% higher than that of neat NBR (0.1373 W (mK)−1). At the filler loading of 9 vol%, the TC of pGO@Ag/pCNT@Ag/NBR composite is 152% that of GO/CNT/NBR composite (0.6660 W (mK)−1). Moreover, due to electron polarization effect of GO and CNT and micro‐capacitor effect of Ag nanoparticles, a large ɛr of 147.12 is attained at 10 Hz for NBR composites. Overall, the development of dielectric polymer materials with high TC is beneficial for enhancing the service life and safety stability of the electronic components. [ABSTRACT FROM AUTHOR]

Silicon (Si) is becoming one of the most promising candidates for lithium‐ion batteries (LIBs) owing to its high theoretical capacity, ultralow lithiation/delithiation voltage, non‐flammability, abundant natural reserves, etc. However, Si particles undergo violent volume expansion/contraction during the charge/discharge cycles, resulting in a series of serious problems such as Si particle pulverization, solid electrolyte interphase film overgrowth, and electrode structure collapse, which severely hinders the application of silicon‐based LIBs. Herein, a composite binder crosslinked by polyacrylic acid and p‐toluene sulfonic acid protonated polyaniline is proposed to improve the electrochemical performance of Si‐based anodes. The cross‐linked composite binder processes 3D networks, fast self‐healing features, and excellent mechanical strength, which can alleviate the damage caused by the expansion of Si particles to the electrodes and protect the structural integrity of the Si‐based electrodes. As a result, the Si‐based anodes with the composite binder present excellent cycle stability (2092.9 mAh g−1 after 300 cycles at 400 mA g−1). In addition, the novel binder reveals well compatibility with commercial Si microparticles. More importantly, the self‐healing Si anode is firstly equipped in an all‐solid‐LIB with solvate ionic liquid‐based quasi‐solid electrolyte and shows excellent cycling stability as well as rate capability. [ABSTRACT FROM AUTHOR]

Purpose: Lymph node (LN) detection is a crucial step that complements the diagnosis and treatments involved during cancer investigations. However, the low-contrast structures in the CT scan images and the nodes' varied shapes, sizes, and poses, along with their sparsely distributed locations, make the detection step challenging and lead to many false positives. The manual examination of the CT scan slices could be time-consuming, and false positives could divert the clinician's focus. To overcome these issues, our work aims at providing an automated framework for LNs detection in order to obtain more accurate detection results with low false positives. Methods: The proposed work consists of two stages: candidate generation and false positive reduction. The first stage generates volumes of interest (VOI) of probable LN candidates using a modified U-Net with ResNet architecture to obtain high sensitivity but with the cost of increased false positives. The second-stage processes the obtained candidate LNs for false positive reduction using 3D convolutional neural network (CNN) classifier. We further present an analysis of various deep learning models while decomposing 3D VOI into different representations. Results: The method is evaluated on two publicly available datasets containing CT scans of mediastinal and abdominal LNs. Our proposed approach yields sensitivities of 87% at 2.75 false positives per volume (FP/vol.) and 79% at 1.74 FP/vol. with the mediastinal and abdominal datasets, respectively. Our method presented a competitive performance in terms of sensitivity compared to the state-of-the-art methods and encountered very few false positives. Conclusion: We developed an automated framework for LNs detection using a modified U-Net with residual learning and 3D CNNs. The results indicate that our method could achieve high sensitivity with relatively low false positives, which helps avoid ineffective treatments. [ABSTRACT FROM AUTHOR]

In this paper, the optimal network dimensions of clustered-routing three-dimensional (3D) wireless sensor networks is provided. The derivation for such dimensions is based upon the minimum energy consumption cost function in the network. Two 3D network geometries are considered, namely, cuboid and cylinder networks. Analysis and simulations have shown that the minimum energy consumption of the two 3D geometries occurs in special dimensions setup. First, for the cuboid network the optimal network dimensions occur at equal length width and height. We refer to this network as cube network. Second, for the cylinder network the optimal case occurs when the radius of the network is around 68.4% of its height. The results are verified using simulations. Low energy adaptive clustering hierarchy protocol has been used as the underlining routing protocol in 3D environment. Total network remaining energy, stable region and network throughput are utilized for performance evaluation of the results. It is shown that networks with optimal dimensions achieve maximum network lifetime and throughput with minimum energy consumption. Moreover, in the optimal network dimensions settings the cylinder network utilizes energy more efficiently and outperforms the cube network in terms of network lifetime and throughput. [ABSTRACT FROM AUTHOR]

To elevate the performance of polymer solar cells (PSC) processed by non‐halogenated solvents, a dissymmetric fused‐ring acceptor BTIC‐2Cl‐γCF3 with chlorine and trifluoromethyl end groups has been designed and synthesized. X‐ray crystallographic data suggests that BTIC‐2Cl‐γCF3 has a 3D network packing structure as a result of H‐ and J‐aggregations between adjacent molecules, which will strengthen its charge transport as an acceptor material. When PBDB‐TF was used as a donor, the toluene‐processed binary device realized a high power conversion efficiency (PCE) of 16.31 %, which improved to 17.12 % when PC71ThBM was added as the third component. Its efficiency of over 17 % is currently the highest among polymer solar cells processed by non‐halogenated solvents. Compared to its symmetric counterparts BTIC‐4Cl and BTIC‐CF3‐γ, the dissymmetric BTIC‐2Cl‐γCF3 integrates their merits, and has optimized the molecular aggregations with excellent storage and photo‐stability, and also extending the maximum absorption peak in film to 852 nm. The devices exhibit good transparency indicating a potential utilization in semi‐transparent building integrated photovoltaics (ST‐BIPV). [ABSTRACT FROM AUTHOR]

To elevate the performance of polymer solar cells (PSC) processed by non‐halogenated solvents, a dissymmetric fused‐ring acceptor BTIC‐2Cl‐γCF3 with chlorine and trifluoromethyl end groups has been designed and synthesized. X‐ray crystallographic data suggests that BTIC‐2Cl‐γCF3 has a 3D network packing structure as a result of H‐ and J‐aggregations between adjacent molecules, which will strengthen its charge transport as an acceptor material. When PBDB‐TF was used as a donor, the toluene‐processed binary device realized a high power conversion efficiency (PCE) of 16.31 %, which improved to 17.12 % when PC71ThBM was added as the third component. Its efficiency of over 17 % is currently the highest among polymer solar cells processed by non‐halogenated solvents. Compared to its symmetric counterparts BTIC‐4Cl and BTIC‐CF3‐γ, the dissymmetric BTIC‐2Cl‐γCF3 integrates their merits, and has optimized the molecular aggregations with excellent storage and photo‐stability, and also extending the maximum absorption peak in film to 852 nm. The devices exhibit good transparency indicating a potential utilization in semi‐transparent building integrated photovoltaics (ST‐BIPV). [ABSTRACT FROM AUTHOR]

In this paper an analytical model of the optimal number of clusters and the corresponding optimal probability are derived for different types of 3D WSN settings utilizing single-hop homogeneous LEACH protocol. Three types of 3D network configurations are analyzed. These include cube, cylinder and sphere network configurations. Energy analysis of these network configurations is done in noise-prone communication environment. The noise is modelled utilizing the probability of reception $p_{r}$. A small value of $p_{r}$ indicates more packets are dropped, which is a sign of large noise. It was shown through analysis and simulation that optimal number of clusters, optimal probability and energy consumption are affected by the geometry of the 3D WSN, noise, and transmission amplification model used. [ABSTRACT FROM AUTHOR]

Abstract: In this study, we report a photoanode consisting of a polymeric/inorganic nanojunction between novel nanostructured 3D C3N4 nano‐networks and BiVO4 substrate. This nanojunction is formed such that 3D C3N4 nano‐networks with a positively charged surface are efficiently anchored on the BiVO4 photoanode with a negatively charged surface. This electrostatic self‐assembly can initiate and contribute to an intimate contact at the interfaces, leading to an enhanced photoelectrochemical activity and stability compared with that fabricated by non‐electrostatic assembly. The C3N4 nano‐network/BiVO4 photoanode achieved a remarkable photocurrent density of 4.87 mA cm−2 for water oxidation at 1.23 V (vs. reversible hydrogen electrode) after depositing FeOOH/NiOOH as oxygen‐evolution co‐catalyst, which is among the highest photocurrent densities reported so far for BiVO4‐based photoanodes. [ABSTRACT FROM AUTHOR]

A general ultrathin-nanosheet-induced strategy for producing a 3D mesoporous network of Co3O4 is reported. The fabrication process introduces a 3D N-doped carbon network to adsorb metal cobalt ions via dipping process. Then, this carbon matrix serves as the sacrificed template, whose N-doping effect and ultrathin nanosheet features play critical roles for controlling the formation of Co3O4 networks. The obtained material exhibits a 3D interconnected architecture with large specific surface area and abundant mesopores, which is constructed by nanoparticles. Merited by the optimized structure in three length scales of nanoparticles-mesopores-networks, this Co3O4 nanostructure possesses superior performance as a LIB anode: high capacity (1033 mAh g−1 at 0.1 A g−1) and long-life stability (700 cycles at 5 A g−1). Moreover, this strategy is verified to be effective for producing other transition metal oxides, including Fe2O3, ZnO, Mn3O4, NiCo2O4, and CoFe2O4. [ABSTRACT FROM AUTHOR]

The N-containing conjugated microporous polymers (CMPs) are synthesized by 2,5-dibromopyrazine or its isomeric pyridazine monomer and 1,3,5-triethynylbenzene via the Pd(0)/Cu(I)-catalyzed Sonogashira-Hagihara cross-coupling polycondensation. The resulting CMPs exhibit diverse porosity and morphology, which reveals macroscopically porous 3D networks for BQCMP-1, agglomerated and amorphous structure for DQCMP-1, arising from the variation of isomeric monomer. In addition, metal ions adsorption capacity of Zn(II), Cr(VI), Ni(II) have been investigated due to the good porosity of CMPs. Compared with Zn(II) and Cr(VI), the adsorption capacity of Ni(II) for BQCMP-1 and DQCMP-1 is maximal, which is 272 mg g−1 and 559 mg g−1. Our study may provide a useful guidance to manipulate CMPs by varying the constitution of isomeric monomer. [ABSTRACT FROM AUTHOR]

The present communication reports a concept battery made by direct contact of magnesium foil with ultralight polyaniline (PANI) foam in the absence of additional electrolyte. Electrical current is allowed to be steadily released from the junction with a specific energy of 646 mWh g−1 and specific capacity of 1247 mAh g−1. Additionally, the battery offers an environmentally friendly route of hydrogen production along with discharging. Mechanistic studies indicated that the ubiquitous galvanic corrosion combined with decomposition of adsorbed trace water in the semi-conducting polymer foam enabled the generation of electricity, which overturns the traditional view. The higher moisture level is conducive to the discharge. This work is believed to open up new possibilities for the design of electrochemical batteries. [ABSTRACT FROM AUTHOR]

Novel 3D hierarchically porous and nitrogen-doped graphene-like microspheres (3D NPGSs) are prepared by precursor-assisted chemical vapor deposition. 3D NPGSs obtained by using Ni microspheres as a structural template exhibit a 3D conductive framework, and have a well-defined porous structure, large surface area and appropriate heteroatom doping, making them suitable for high-performance storage of lithium ions. Consequently, a good rate capability and excellent cycle performance are achieved using the 3D NPGSs as anodes for lithium storage, and a high reversible capacity of 840 mA h g−1 is obtained after 200 cycles. For a further capacitance boost, a thin layer of iron oxide nanoparticles is deposited onto the 3D NPGSs. The resulting 3D FeO x-NPGS electrode exhibits a stable reversible capacity up to 1343 mA h g−1 after 100 cycles. [ABSTRACT FROM AUTHOR]

Although stateless greedy routing is well investigated in 2D wireless sensor networks (WSNs), it is widely believed to be impossible in 3D. In this paper, we aim at overcoming the impossibility through a distributed parametrization that equips a WSN with virtual coordinates favoring greedy routing. We propose a fundamentally new parametrization to embed the network domain, the resulting embedding domain allows greedy routing to have guaranteed delivery. We also present localized algorithms to realize this map in WSNs. To combat the load concentration caused by greedy routing that applies the distance greedy principle, we further propose tunable greedy routing, which relies on tuning a parameter in the greedy objective to naturally balance routing load. These two proposals form our Greedy Routing through dIstributed Parametrization (GRIP). We prove the correctness and efficiency of GRIP and use simulations to evaluate its performance in terms of complexity, load balancing, and energy efficiency. [ABSTRACT FROM AUTHOR]

Construction of stable 3D networks directly on the inner wall of microchannels is of great importance for various microfluidic applications. 3D nest-like networks with large contact surface areas and excellent structural stability are fabricated via a facile, template-free, continuous fluid construction process directly in confined microchannels. Bovine serum albumin (BSA) is chosen as a model albumin to test the adsorption of the network modified microchannel to the target albumin. The high structural stability of the networks is confirmed both by finite element analysis (FEA) simulation and recycling experiments for BSA enrichment. ZnS shells are fabricated based on the original 3D Zn(OH)F networks through in situ chemical conversion. The nest-like networks decorated with Ag nanoparticles (NPs) serve as 3D substrates for surface-enhanced Raman scattering (SERS), exhibiting excellent sensitivity for rapid detection of trace 10−12 mol L−1 (1 pM) BSA. Three different gap sizes between Ag NPs in the 3D geometry create a large number of SERS hot spots that contribute to the high sensitivity of the networks. Furthermore, a transparent, flexible, microfluidic device containing the 3D nest-like structures exhibits excellent recyclability and flexible stability for trace BSA enrichment, showing potential for application in online SERS detection. [ABSTRACT FROM AUTHOR]

Neighbor-Every-Theta (NET) graphs are such that each node has at least one neighbor in every theta angle sector of its communication range. We show that for θ < #x03C0;, NET graphs are guaranteed to have an edge connectivity of at least [2#x03C0;/θ], even with an irregular communication range. Our main contribution is to show how this family of graphs can achieve tunable topology control based on a single parameter θ. Since the required condition is purely local and geometric, it allows for distributed angle-only topology control. For a static network scenario, a power control algorithm based on the NET condition is developed for obtaining k-connected topologies and shown to be significantly efficient compared to existing schemes. In the controlled deployment of a mobile network, control over positions of nodes can be leveraged for constructing NET graphs with desired levels of network connectivity and sensing coverage. To establish this, we develop a potential fields-based distributed controller and present simulation results for a large network of robots. Last, we extend NET graphs to 3D and provide an efficient algorithm to check for the NET condition at each node. This algorithm can be used for implementing generic topology control algorithms in 3D. [ABSTRACT FROM AUTHOR]

Hydrogen gas (H2) is being intensively proposed as a next-generation clean energy owing to the depletion of fossil fuels. Electrochemical water splitting is one of the most promising processes for hydrogen production. Furthermore, many efforts focusing on electrochemical water splitting have been made to develop low-cost, electrochemically active, and stable catalysts for efficient hydrogen production. MoS2 has emerged as an attractive material for developing catalysts for the hydrogen evolution reaction (HER). Hence, in this study, we design hierarchically ordinated two-dimensional (2D) MoS2 nanosheets on three-dimensional (3D) reduced graphene oxide (rGO) (H-2D/3D-MoS2-rGO) aerogel structures as a new class of electrocatalysts for the HER. We use the one-pot hydrothermal synthesis route for developing high-performance electroactive materials for the HER. The as-prepared H-2D/3D-MoS2-rGO contains a unique 3D hierarchical structure providing large surface areas owing to the 3D porous networks of rGO and more active sites owing to the many edge sites in the MoS2 nanosheets. In addition, the H-2D/3D-MoS2-rGO structure exhibits remarkable electrochemical properties during the HER. It shows a lower overpotential than pure MoS2 and excellent electrochemical stability owing to the large number of active sites (highly exposed edge sites) and high electrical conductivity from the rGO structure. [ABSTRACT FROM AUTHOR]

Easy and high efficient methods are in great demand to obtain polyimide (PI) composites with high thermal conductivity in the electronic packaging field. In this work, PI/boron nitride (BN) composites with high thermal conductivity are easily fabricated. Tightly connected and well‐arranged BN platelets construct effective 3D thermally conductive networks in the PI matrix upon hot pressing, after BN platelets are coated on the surface of PI granules by the help of a kind of PI adhesive. The thermal conductivity of the PI/BN composites reaches as high as 4.47 W mK–1 at a low BN loading of 20 vol%, showing an enhancement of 2099%, compared to pure PI. Such enhancement of the thermal conductivity is the highest compared with the results in the open literature. Our work is a good example that utilized the sufficient physical connection (aggregates) of thermally conductive fillers to significantly promote the thermal conductivity of polymer composites. [ABSTRACT FROM AUTHOR]

Inspired by Nature, Marisol Martín‐González and co‐workers (article number 1800408) explore the fabrication of flexible distributed Bragg refractors from commodity thermoplastic polymers like polyethylene, creating a hydrophobic metamaterial with consistent structural colour in different view directions. These large three‐dimensional polymer networks open new possibilities for the use in sensing, photonics, filtering or as scaffold for other materials. [ABSTRACT FROM AUTHOR]

The synthesis of flexible photonic materials, by sustainable and scalable methods, is proved to be a difficult task for the materials science and industrial communities. Alongside, the modern society has also grown a strong dependence on polymeric materials, demanding superpolymers that combine functionality and cost with superior after‐use properties. The path for accomplishing this aim is made possible by mimicking nature through the merging of self‐ordered nanostructures and a commodity thermoplastic, resorting to basic fabrication infrastructure. This work presents the development of a flexible material that exhibits tunable structural color due to its 3D polyethylene based nanonetwork. These nanonetworks are hydrophobic, and change color depending on the refractive index of the material filling their voids. This developed flexible metamaterial is projected to open opportunities for the fabrication of economically affordable (around 0.008 € cm−2) and solvent‐free photonic nanostructures with multipurpose applications such as sensing, energy saving, clothing, and photovoltaics, among others. In this work, a simple and scalable method for the fabrication of polyethylene‐based Bragg refractors is explored by a combination of pulse aluminum anodization and polymer melt infiltration. A 3D polymeric network is fabricated. This metamaterial is flexible, hydrophobic and with tunable Bragg‐reflector properties. Its cost‐effectiveness makes it suitable for large production with multipurpose applications. [ABSTRACT FROM AUTHOR]