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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]

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 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.

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]

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.

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.

Understanding the mechanisms underlying cell-surface interaction is of fundamental importance for the rational design of scaffolds aiming at tissue engineering, tissue repair and neural regeneration applications. Here, we examined patterns of neuroblastoma cells cultured in three-dimensional polymeric scaffolds obtained by two-photon lithography. Because of the intrinsic resolution of the technique, the micrometric cylinders composing the scaffold have a lateral step size of ~200 nm, a surface roughness of around 20 nm, and large values of fractal dimension approaching 2.7. We found that cells in the scaffold assemble into separate groups with many elements per group. After cell wiring, we found that resulting networks exhibit high clustering, small path lengths, and small-world characteristics. These values of the topological characteristics of the network can potentially enhance the quality, quantity and density of information transported in the network compared to equivalent random graphs of the same size. This is one of the first direct observations of cells developing into 3D small-world networks in an artificial matrix.

• Attention guiding is significant for video saliency prediction based on 3D CNN. • A spatiotemporally attentive 3D CNN for robust video saliency prediction is proposed. • An adaptive upsampling module for refining spatial features is proposed. • A frame-wise attention module for propagating temporal features is proposed. • The effectiveness of the proposed method is comprehensively evaluated. 3D fully convolutional networks (FCN), which jointly leverage the spatial and temporal cues, have achieved great success in video saliency prediction. However, they still have limitations in some challenging cases, e.g. fixation shift. To address this issue, we propose a SpatioTemporally Attentive 3D Network (STA3D) to selectively propagate the significant temporal features and refine the spatial features in 3D FCN for video saliency prediction. Extensive experiments on three standard datasets demonstrate the superiority of the proposed model against the state-of-the-art. [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]

With the growing challenges of modern electronics in heat dissipation, developing thermal management materials with high thermal conductivity and electrical insulation property remains an important issue for electronics. In this work, a novel three-dimensional network (3D) of boron nitride/reduced graphene oxide (BN/rGO) with covalent bond connections were fabricated by using the surface modification and ice-templated methods. The as-prepared boron nitride/reduced graphene oxide/nature rubber composites (BN/rGO/NR) possessed an enhanced through-plane thermal conductivity of 1.28 W m−1 K−1 and satisfactory electrical insulation at a low filler loading of 4.9 vol%. The results demonstrated that the covalent bond connections and three-dimensional networks of fillers greatly reduced the interfacial thermal resistance as well as phonon scatterings at the filler/filler and filler/matrix interface simultaneously. More importantly, this strategy provided a creative insight to the design of advanced thermal management materials and also presented a bright application prospect for next-generation electronic packing. BN and rGO were connected by the covalent bonds through using the surface modified method. BN/rGO/NR composites were fabricated by the ice-templated and vacuum-assisted method. Image 1 [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.

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 VO 2 as one of the most prospective cathode materials applied for lithium-ion batteries, has appealed increasing attentions owing to its high theoretical specific capacity, unique tunnel structure, as well as low cost. Among multiple methods to optimize the electrochemical performances of VO 2 (B), heteroatom-doping has attracted increasing interests owing to its efficiently adjusting the microstructure and interplanar distances of VO 2 (B). Here, W-doped VO 2 (B) nanosheets-built 3D networks are obtained readily via a hydrothermal route by oxalic acid reduction of vanadium pentoxide. The resultant 3D networks possess ultrathin nanowalls, interconnected structure and enlarged tunnels, which are advantageous for the easy access of electrolyte and fast diffusion of lithium ions. As a consequence, high reversible specific capacity of 304 mAh g−1, ultrahigh rate capability (200 mAh g−1 at 2 A g−1), and high-temperature electrochemical performances are achieved as the 3D networks are applied for lithium storage. [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: 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]

In order to improve the conductivity and electrochemical activity, Co 9 S 8 nanoparticles anchored in three-dimensional carbon nanosheet networks (3D Co 9 S 8 @CNNs) are fabricated by a simple strategy with the assistance of NaCl. Combining the advantages of nanoscale and porous structure, 3D Co 9 S 8 @CNNs can retard the aggregation of Co 9 S 8 nanoparticles, provide abundant electrochemical active sites, as well as accommodate the mechanical stress during the cycling of lithium ion batteries (LIBs) or sodium ion batteries (SIBs). Thus, when evaluated as an anode for LIBs, the as-prepared 3D Co 9 S 8 @CNNs electrode exhibits outstanding electrochemical performance with a high reversible capacity of 935 mAh g −1 after 200 cycles at 0.25 A g −1 . As for SIBs, it also delivers superior cycling stability with a capacity of 249 mAh g −1 after 50 cycles at 0.1 A g −1 . These results demonstrate that 3D Co 9 S 8 @CNNs composite has potential to be utilized as an anode material for LIBs/SIBs with enhanced electrochemical performance. [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]

• Luminescent composites with high-thermal-conductivity is achieved via 3D-hBN network. • The mechanism of thermal conduction enhancement is explained by numerical simulation. • Optical performance of the proposed luminescent composites is tested. • Laser-excited white lighting with excellent cooling performance is demonstrated. Laser-excited white lighting, which is achieved by laser diodes and phosphor converters, has garnered increasing interest in recent years due to their high-power and high-brightness characteristics. Nevertheless, two long-standing thermal issues remain formidable: first, the photoluminescent phosphors also generate heat due to the Stokes loss, which are the second heat source in the packaging but long ignored; second, the phosphors are embedded in low-thermal-conductivity silicone and the generated heat is rather inefficient to dissipate. As a result, the accumulated heat leads to high temperature in phosphor particles and even thermal quenching, which deteriorate the luminescence, chromaticity, and reliability. In this work, these problems are successfully addressed by establishing three-dimensional (3D) boron nitride (BN) networks to cool the silicone-embedded phosphor particles in a facile and scalable method. When lighted under the driven current of 900 mA, the working temperature of phosphor layer is dramatically decreased by 95.2 °C with the 3D-BN network without sacrificing the luminescence and chromaticity. Such strategy with excellent cooling performance, high reliability, and easy scalability may hold great promise for broader optoelectronics applications beyond laser-excited white lighting. [ABSTRACT FROM AUTHOR]

Fibrin, the prominent extracellular matrix in early wound tissue, is discussed to influence immune cells and healing. The nature of fibrinogen/fibrin to form fibrillary networks is frequently exploited to engineer microenvironments for cellular analysis. This study focuses on revealing the correlation of fibril formation kinetic and the resulting network microstructure of engineered 3D fibrin networks. Different concentrations of fibrinogen (1-3 mg mL -1 ), thrombin (0.01-0.15 U mL -1 ), sodium chloride (40-120 mm), and calcium chloride (1-10 mm) are applied to assess the impact on the fibril growth kinetics by turbidity analysis and on the resulting fibril and pore diameter by laser scanning microscopy. The results highlight a direct influence of the sodium chloride concentration on fibrillation kinetics and reveal a strong correlation between fibrillation kinetics and network microstructure. With the assumption of a first-order growth kinetic, an increase of the growth constant k (0.015-0.04 min -1 ) is found to correlate to a decrease in fibril diameter (1-0.65 µm) and pore diameter (11-5 µm). The new findings enable an easy prediction of 3D fibrin network microstructure by the fibril formation kinetic and contribute to an improved engineering of defined scaffolds for tissue engineering and cell culture applications., (© 2022 The Authors. Advanced Healthcare Materials published by Wiley-VCH GmbH.)

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]

The increasing interest in using sensor networks in applications for underwater surveillance and oceanic studies underscores the importance of solving the coverage and connectivity issues in 3D wireless sensor networks (WSN). In particular, the problem of supporting full coverage, while ensuring full network connectivity is a fundamental one for such applications. Unfortunately, designing a 3D network is significantly more difficult, as compared to designing a 2D network. Previously, it has been shown that dividing a 3D space into identical truncated octahedral cells of radius equal to the sensing range and placing a sensor at the center of each cell, provides full coverage with minimum number of nodes [2] . But this requires the ability to deploy and maintain sensor nodes at such particular locations. In many environments, this is very difficult, if not impossible, to do. In this paper, we investigate the coverage and connectivity issues for such 3D networks, especially underwater networks, while assuming random and uncontrollable node locations. Since node location can be random, redundant nodes have to be deployed to achieve 100% sensing coverage. However, at any particular time, not all nodes are needed to achieve full sensing coverage. As a result, a subset of the nodes can be dynamically chosen to remain active at a time to achieve sensing coverage based on their location at that time. One approach to achieve this goal in a distributed and scalable way is to partition the 3D network volume into virtual regions or cells, and to keep one node active in each cell. Our results indicate that using cells created by truncated octahedral tessellation of 3D volume minimizes the number of active nodes. This scheme is fully distributed, and so it is highly scalable. By adjusting the radius of each cell, this scheme can be used to achieve k -coverage, where every point inside a network has to be within the sensing range of k different sensor nodes. We analyze and compare the performance of these schemes for both 2D and 3D networks. While for 1-coverage, the 3D scheme is less efficient than the 2D scheme, the performance of 3D scheme improves significantly as compared to 2D scheme for k -coverage, for values of k is larger than 1. As a result, such a distributed and scalable scheme can be more useful in 3D networks than in 2D networks. Although this paper targets in particular 3D underwater networks, much of our results are applicable to other 3D networks, such as for airborne applications, space exploration, and storm tracking. [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]

• An air-bubbles-assembly strategy was proposed for constructing 3D network. • In-situ heat dissipation pathways were established inside the WLEDs. • The 3D/hBN network reduced the working temperature of QDs by 57.3°C. • FEM analysis was performed to visualize the effectiveness of the 3D network. The non-radiative electron transitions of Quantum dots (QDs) in White light-emitting diodes (WLEDs) not only generates thermal phonons with temperature rise but also degrades their photonic properties. These nanoscale heat sources are usually embedded in low-thermal-conductivity polymer matrix, which is difficult for building efficient heat dissipation pathways without sacrificing the optical performance simultaneously. Herein, we reported an air-bubbles-assembly strategy to construct three-dimensional (3D) thermal dissipation network inside the QDs-WLEDs. Owing to the lateral expulsion of massive microscale air-bubbles, an interconnected hexagonal boron nitride (hBN) network was established under an extremely low hBN loading of 2.74 wt%. With this efficient 3D/hBN network, the highest working temperature of QDs was dramatically decreased by 57.3°C at 700 mA. More than that, the 3D/hBN-WLEDs also show high luminous efficacy of 84.6 lm/W as well as superior color rendering index of Ra = 94.1 and R9 = 93.8, which are comparable to those of traditional WLEDs. The proposed strategy is expected to pave a new door for targeting cooling QDs and other photoluminescent nanoparticles at high-power applications. [ABSTRACT FROM AUTHOR]

Abstract: Copper(II) complexes of 2-di1H-2-imidazolylmethylmalonate (DIMMAL) have been studied by potentiometric methods. The data revealed that the and species are prevalent in the studied pH range. Moreover, this paper reports the synthesis, structure solution and spectroscopic characterization of two new DIMMAL containing complexes, (NH4)2[Cu(DIMMAL)2]·4H2O (1) and [Cu(DIMMAL)(en)(H2O)]·5H2O (2). The structure of compound 1 consists of centrosymmetric mononuclear anionic [Cu(DIMMAL)2]2− units, cations and lattice water molecules, in which DIMMAL2− acts as a tridentate ligand through two imidazole nitrogen atoms and one oxygen atom from a carboxylate group. The crystal structure of compound 2 is built up from mononuclear neutral [Cu(DIMMAL)(en)(H2O)] and water molecules of crystallization. In both cases the MBBs are interconnected into 3D networks by multiple H-bonding paths and aromatic–aromatic interactions, which play a determinant role in the modulation of the crystal packing. EPR spectra are indicative of an essentially ground state for the copper(II) ions in both compounds (CuN4O2 chromophores). [Copyright &y& Elsevier]

Four new 3D supramolecules of Co(II), [cis-Co(H2O)4(fum)]n(H2O)n (violet) (1); [trans-Co(H2O)4(fum)]n (pink) (2); [Co(H2O)4(bpy)]n(fum)n(4H2O)n (pink) (3) and [Co(H2O)6(fum)(hmt)2·4H2O]n (pink) (4) [fum=fumarate, bpy=4,4′-bipyridine, hmt=hexamethylenetetramine, also known as urotropine] have been synthesized and characterized by X-ray single crystal structure determination, IR, electronic spectra and thermogravimetric analyses. Complexes 1 and 2 are obtained as a mixture from the same reaction. Structure analyses show that they consist of &z.sbnd;Co(H2O)4&z.sbnd;fum&z.sbnd; coordination polymers with carboxylate connected in a bis-monodentate fashion with a cis-(1) and trans-(2) geometry around Co(II). Both the compounds show strong intrachain as well as interchain hydrogen bonding interactions between the uncoordinated oxygens of the dicarboxylate and the coordinated water molecules to produce 3D supramolecular networks. Complex 3 gives likewise origin to a hydrogen bonded 3D framework, comprising of 1D &z.sbnd;Co(H2O)4&z.sbnd;(bpy)&z.sbnd; coordination chains with encapsulated fumarate and lattice water molecules. The structure of compound 4 comprises of Co(H2O)6 2+ and fumarate ions, hmt, and water molecules, all connected through an extensive hydrogen bonding to form a 3D network. All the complexes upon heating lose water molecules yielding blue species, which revert the process on exposure to humid atmosphere. [Copyright &y& Elsevier]