Search

In recent years, adhesive thermal interface materials have attracted much attention because of their reliable adhesion properties on most substrates, preventing moisture, vibration impact, or chemical corrosion damage to components and equipment, as well as solving the heat dissipation problem. However, thermal interface materials have a huge contradiction between strong adhesion and high thermal conductivity. Here, we report a polymer-based thermal interface material consisting of polydimethylsiloxane/spherical aluminum fillers, which possesses both adhesion properties (adhesion strength of 3.59 MPa and adhesion toughness of 1673 J m–2and enhanced thermal conductivity of 3.90 W m–1K–1). These excellent properties are attributed to the modified chain structure by introducing acrylate accelerators into the polydimethylsiloxane network, thereby striking a balance between interfacial toughness and intrinsic dissipation. The addition of thermally conductive aluminum fillers not only increases the thermal conductivity but also improves the bulk energy dissipation of the thermal interface material. This work provides a novel strategy for designing a novel thermal interface material, leading to new ideas in long-term applications in high-power electronics.

With the progressive demands of electronics, advanced electromagnetic interference (EMI) shielding technology are desired to protect electronics against risk from EMI radiation under various conditions. In this work, a new kind of 3-D conformal EMI shielding technology based on a polymer composite film with high stretchability and electrical conductivity was proposed. The conductive composite film contains thermal plastic polymer matrix, metallic fillers, and additives, which exhibits excellent conductive, stretchable, and adhesive properties, and provides 3-D conformable capability on a printed circuit board assembly (PCBA). The conductive composite film shows a high EMI shielding effectiveness (SE) value of 72 dB in the 30–3000 MHz and 91 dB in the 8.2–12.4 GHz at thickness of $65~\mu $ m, and relative near-field SE value of exceed 35 dB in 500–6000 MHz. Obviously, this novel conformal EMI shielding technology will be a promising candidate for application in board-level shielding (BLS).

Constipation is a common and prevalent digestive system disease in clinical practice, which seriously affects human physical and mental health. Currently, chemical drugs have good short-term therapeutic effects. However, because of their adverse reactions, easy recurrence after drug discontinuation, and dependence with long-term use, the long-term efficacy is unsatisfactory. The pathogenesis of constipation is mainly attributed to dysfunction of zang-fu organs and imbalance of qi-blood and yin-yang, with the syndrome being asthenia in origin and asthenia in superficiality. Aloeis a traditional Chinese medicine with cold properties and a bitter taste, and one of the most commonly used herbs for constipation. Based on Aloeand its monomer components, combined with the existing compatibility studies of Aloeand several Chinese patent drugs represented by Aloe, this paper comprehensively and systematically introduced the research progress of Aloeand its compatibility prescriptions in the treatment of constipation from basic experiments to clinical observations, providing theoretical basis and medication guidance for the clinical rational application of Aloeand its prescriptions in the treatment of constipation. At the same time, it also provides the direction for future research on the mechanism of Aloein the treatment of constipation.

Different types of electron transfers (ETs) underlie the versatile use of various solid viologen-derived compounds, which is still insufficiently understood and difficult to control. Here, we demonstrate an effective strategy for modulating the key ET process in crystalline metalloviologen compounds (MVCs). By adjusting the coordinated transition metal ions bearing different electronic structures (e.g., d5, d7, d10), three MVCs (i.e., Mn-1, Co-2, and Cd-3) with highly consistent coordination environments have been synthesized successfully. Surprisingly, whether the photochromism (energy-induced ET mechanism) or the specific analyte recognition (molecule-induced ET mechanism), compound Cd-3exhibits obvious photochromic behavior and differential dimethylamine detection. Combined detailed structural analysis with theoretical calculations, such unique ion-dependent properties, were correlated to the fine modulation of the electron density of the bipyridinium cores by metal ions. Additionally, thanks to the delicate recognition of dimethylamine vapor, a convenient test strip Cd-3-PANwas prepared as a sensitive biogenic amine sensor for evaluating the real-time freshness of seafood.

In recent years, grid-connected power electronic converters have had a continuously increasing influence on dynamics of bulk power systems. Consequently, modelling of power electronic converters has become critical to modern power system stability studies. However, few existing studies can systematically model switching control characteristics or handle discontinuous state variables of power electronic converters. To address these limitations, this article proposes a general four-step analytical switching modelling method of grid-connected converters, which involves formulating holonomic differential-algebraic equations of the converter including all switching actions, transforming all state-dependent switching conditions into time-dependent ones, deriving differential equations of the system for all time periods, and analyzing the continuity of each state variable at all switching moments. An example model is established and then evaluated through detailed simulations to verify the effectiveness of the proposed modelling method. The revealed switching-induced transient instability mechanism and corresponding stability enhancement method based on the example model demonstrate the practicality of the proposed method and emphasize the importance of considering switching characteristics in analytical modelling of power electronic converters.

• Resolving spatially and identifying chemical atoms in layered GeS material. • GeS nanosheets with a thickness of 2, 3 layers exhibit high optical nonlinearity. • Realizing a passively mode-locked fiber laser based on a GeS saturable absorber. • 2D GeS is a promising nonlinear material for mid-infrared waveband applications. Germanium sulfide (GeS) represents a typical two-dimensional (2D) material that exhibits fascinating prospects for optoelectronic applications, and the understanding of its atomic-scale structure is crucial to tailoring its desired photonic properties. Here, we systematically investigate the atomic-scale structure of GeS and its nonlinear optical absorption properties. The GeS nanosheets of a thickness of 2, 3 layers exhibit high optical nonlinearity with an effective nonlinear coefficient of -0.318 cm/GW, larger than that of black phosphorous by three orders, which can be applied for the generation of ultrashort-pulse lasers. We fabricate a Tm-doped passively mode-locked fiber laser based on a GeS saturable absorber and achieve a fundamental repetition rate of 9.7 MHz and a pulse duration as short as 1.56 ps at ∼2 µm. These findings suggest that 2D GeS nanosheets could be an efficient nonlinear material in the mid-infrared waveband with potential applications in integrated nonlinear photonics. [Display omitted] [ABSTRACT FROM AUTHOR]

Interest in electrocatalytic bioconjugation reactions has surged, particularly for modifying tryptophan and tyrosine residues in proteins. We used a cost-effective graphite felt electrode and low-current methodology to achieve selective bioconjugation of tryptophan with thiophenols, yielding up to 92%. This method exclusively labeled tryptophan residues and incorporated fluorinated tryptophan for NMR analysis. Eight polypeptides, including lanreotide and leuprorelin, were effectively coupled, demonstrating the method’s versatility and potential for novel diagnostic and therapeutic agents.

Carbon nanotubes (CNTs) can be regarded as a potential platform for transmembrane drug delivery as many experimental works have demonstrated their capability to effectively transport bioactive molecules into living cells. Within this framework, the loading of a peptide drug onto either the interior or exterior of CNTs has gained considerable interest. This study aims to conduct a comprehensive comparison of these two loading methods. To this end, we performed molecular dynamics simulations and the umbrella sampling technique to investigate the interaction energy, conformational changes, and free energy changes of a model peptide drug containing α-helical structure interacting with the inner or outer walls of a 14.7-nm-long (20,20) CNT. Our finding reveals that, for a tube of such dimensions, it is thermodynamically more favorable for the peptide to be loaded onto the inner tube wall than the outer tube wall, primarily due to a larger free energy change for the former strategy. Conversely, unloading the drug from the tube interior poses greater challenges. Moreover, the tube’s curvature plays an essential role in influencing the conformation of the adsorbed peptide. Despite the relatively weaker van der Waals interaction between the CNT exterior and the peptide, loading the peptide onto the exterior may induce significant conformational changes, particularly affecting the peptide’s α-helix structure. In contrast, loading of the peptide on the CNT interior could maintain most of the α-helical content. CNTs do not typically attract specific peptide residues, with adsorbed groups primarily determined by the peptide’s configurations and orientations. Finally, we offer a guideline for selecting an optimal loading strategy for CNT-based drug delivery.

Stress-induced anisotropy has been applied for FeSiBCuNb nanocrystalline alloy ribbons in transformers with large direct current (DC) component. However, the physical mechanism of anisotropy induced by stress annealing during crystallization remains controversial. Here, a systematic study was conducted on the microstructure, residual stress state, dynamic domain structure and properties of the stress-annealed FeSiBCuNb nanocrystalline ribbons. Present results demonstrate that, the increase of the applied stress greatly increases the residual tensile stress and induces lattice distortion, which acts as pinning site during magnetization, resulting in enhanced domain-wall energy and narrower wall width. Meanwhile, stress annealing promotes the flattening of hysteresis loops and decreases the effective permeability, which improves the DC-bias characteristics of the ribbons, thereby promoting the transition from “hard saturation” to “soft saturation” behavior. Also, stress-induced grain refinement is beneficial to obtaining high hardness. Owing to the stress-induced anisotropy, the stress-annealed sample with applied stress of 113 MPa exhibits excellent combined properties, including low constant effective permeability of 438 at wide frequency range (1 kHz–8 MHz), high DC-bias capability of 74% (30 Oe), low power loss of 49 kW/m3(100 mT, 100 kHz), and high hardness of 644 HV. This discovery provides an insightful understanding of stress-induced anisotropy mechanism on the high-performance Fe-based nanocrystalline alloys.

Asari Radixet Rhizoma(ARR), also known as Xixin, has been broadly used as a traditional herbal medicine in East Asia and is an important component of classic prescriptions, including Mahuang Fuzi Xixindecoction. It was initially classified as a “top grade” herb in ancient Chinese Pharmacopeia, Shennong’s Materia Medica. Volatile oils, lignans, fatty acids, flavonoids, and nitrogen-containing compounds are the main ARR components. Previous pharmacological studies have shown that ARR exerts beneficial effects in humans for treating headaches, toothaches, and several inflammatory diseases by dispelling wind and cold, alleviating pain, and eliminating phlegm. However, “the dosage of ARR should not exceed one coin (approximately 3.75 grams),” as stated in Shizhen Li’s Compendium of Materia, which emphasized the considerable ARR toxicity and significantly constrained its clinical application. This review aimed to consolidate recent advancements in the understanding of the toxic ARR components. Additionally, we provide an overview of the hepatotoxicity, genotoxicity, neurotoxicity, and pulmonary toxicity of ARR and discuss the underlying molecular mechanisms. This study reviews the limitations of current studies and enhances our understanding of the toxic effects of ARR from the perspective of its toxic components and mechanisms, thereby providing a theoretical basis for the rational clinical practice of ARR-based medications.

Although intense efforts have been devoted to the development of thermally conductive epoxy resin composites, most previous works ignore the importance of the contact thermal resistance between epoxy resin composites and mating surfaces. Here, we report on epoxy resin/hexagonal boron nitride (h-BN) composites, which show low contact thermal resistance with the contacting surface by tuning adhesion energy. We found that adhesion energy increases with increasing the ratio of soybean-based epoxy resin/amino silicone oil and h-BN contents. The adhesion energy has a negative correlation with the contact thermal resistance; that is, enhancing the adhesion energy will lead to reduced contact thermal resistance. The contact thermal conductance increases with the h-BN contents and is low to 0.025 mm2·K/W for the epoxy resin/60 wt % h-BN composites, which is consistent with the theoretically calculated value. By investigating the wettability and chain dynamics of the epoxy resin/h-BN composites, we confirm that the low contact thermal resistance stems from the increased intermolecular interaction between the epoxy resin chains. The present study provides a practical approach for the development of epoxy resin composites with enhanced thermal conductivity and reduced contact thermal resistance, aiming for effective thermal management of electronics.

Constipation is common in the diseases of the digestive system in clinics. With the change in diet structure and the increase in life pressure, the prevalence rate increases year by year. In traditional Chinese medicine (TCM), the location of the disease of constipation is in the large intestine, which is related to the dysfunction of lung, spleen, liver, kidney and other viscera. Its pathogenesis is conductive dysfunction of large intestine. Based on the theory, Shouhui Tongbian Capsule (SHTB) is composed of eight traditional Chinese medicines, including Polygoni multiflori Radix(Heshouwu in Chinese), Aloe(Luhui in Chinese), Cassiae Semen(Juemingzi in Chinese), Ginseng Radixet Rhizoma(Renshen in Chinese), Lycii Fructus(Gouqizi in Chinese), Asini Corii Colla(Ejiao in Chinese), Aurantii Fructus Immaturus(Zhishi in Chinese), and Atractylodis Macrocephalae Rhizoma(Baizhu in Chinese), which could help to release excessive turbid, and nourishing yinand supplementing qiin the treatment. This study has been carried out to review the latest advances of SHTB in the treatment of constipation. The results showed that significant effect of SHTB was found in the treatment of constipation, such as functional constipation, and constipation associated with tumor chemotherapy, colitis, type 2 diabetes and chronic cardiac failure. Besides, obvious adverse reactions were not observed. SHTB could effectively treat five types of constipation, provide direction for the future exploration of SHTB in the treatment of other types of constipation.

Metal polyarene complexes have attracted great attention in recent years because of their appealing electronic structures and readily tunable properties and reactivity. While main group and transition metal polyarene complexes have been well studied with various degrees of reduction and different coordination modes, f-block metal polyarene complexes are rare. Here we report the synthesis of a series of uranium polyarene complexes supported by ferrocene diamide ligands. X-ray crystallography shows that the structures of uranium polyarene complexes are dependent on the topology of polyarenes. While linear polyarenes form mononuclear compounds, nonlinear polyarenes prefer an inverse-sandwich structure with a μ-η6,η6-coordination mode. Combined experimental and computational studies unveil that mononuclear uranium polyarene complexes are best described as bidentate with a three-center two-electron (3c-2e) σ bond, whereas inverse-sandwich uranium polyarene complexes are bound through two δ bonds. The correlation between the topology of polyarenes and the coordination mode of uranium polyarene complexes can be rationalized by the electronic structures and bonding interactions as well as the relative energies of coordination isomers.

Slit dams, as effective open barrier structures, are widely used to intercept granular flows. To investigate the blocking efficiency and impact force magnitude of slit dams, physical experiments are conducted to calibrate numerical simulation tests. In this study, a flume model without lateral confinement is established, and various slit dam configurations are designed to evaluate the effects of pillar spacing, number of pillar rows, and pillar staggering on the blocking efficiency and impact load of granular flows. The results indicate that all three factors are closely related to granular flow blocking and impact forces. (1) The pillar spacing is inversely proportional to the blocking efficiency and impact peak value; as the blocking efficiency decreases, the impact peak value and static passive earth pressure also decrease accordingly. (2) Increasing the number of rows reduces the blocking efficiency and impact force of the first row of slit dams. Compared to a single row of pillars, a double row of pillars reduces the impact force by 3.20%, while a triple row of pillars reduces the impact force by 2.39% compared to a double row. The impact peak value and passive earth pressure on the side pillars increase due to the dispersed granular flow. (3) The staggered pillar structure reduces the blocking efficiency of the first row of slit dams while simultaneously lowering the impact peak value of the front row. The staggered structure can reduce the impact peak value by 1.22%. (4) The experimental results laterally demonstrate that the multi-structural arrangement of slit dams increases particle collisions within the dam body, reducing the impact on the first row of dams and causing some particles to move forward. These findings provide a technical basis for the optimized design of open slit dams, enabling them to exhibit higher performance during the design phase.

In recent years, geosynthetic-reinforced pile-supported (GRPS) embankments have gathered increasing attention in the scientific community for their effectiveness in improving soft ground. This study aims to investigate the load transfer of double-layer GRPS embankments using the discrete element method (DEM), with a focus on soil arching effects and membrane effects. A coefficient, denoted as ηand defined as h/H, was introduced to study the influence of the distance between two geosynthetics on load transfer. The results indicated: (1) Double-layer GRPS embankments demonstrated uniform load transmission downwards, thereby reducing the large deformation zone within the embankment fill. (2) Maximum tension in geosynthetics occurred at the edges of pile caps in both single-layer and double-layer GRPS embankments. However, double-layer GRPS embankments effectively mitigated the maximum tension in geosynthetics. (3) Double-layer GRPS embankments minimized soil arching formation within the embankment while enhancing membrane effects. (4) With increasing η, soil arching gradually formed between the two layers of geosynthetics. (5) Above a ηthreshold of 0.1, the maximum tension in the lower layer of geosynthetics significantly exceeded that in the upper layer.

With the rapid growth of data scale and limitation on bandwidth in networks, coding scheme in distributed storage system is becoming the research hotspot. The piggybacking framework can solve the problem of high repair bandwidth of traditional MDS codes in distributed storage systems, while satisfying the properties of maximum-distance-separability (MDS) and high code rate which can guarantee the high storage efficiency. Several piggybacking designs have been proposed mainly aiming at the repair of systematic nodes. For the repair of parity nodes, these designs either adopt the traditional MDS code decoding or reduce the repair bandwidth by multiplying the number of substripes, which is not ideal in practice. In this paper, based on an single instance of repair efficiency piggybacking scheme, some specially designed simple finite field additions are introduced to encode parity symbols. The new design scheme is called NREPB. It can effectively reduce the repair bandwidth of parity nodes while ensuring no side-effect on the repair of systematic nodes. And the number of substripes in NREPB remains small, which is important in practical applications.

Considering the wave function, the decreasing thickness of ultrathin body from 10 nm down to 2 nm increases the intrinsic gate capacitance since the centroid of carriers located at the center of the channel is extremely close to the channel/oxide interface in the ultrathin body. By the self-consistent Poisson–Schrodinger solver with 6-kp parameters calibrated with nonlocal empirical pseudo-potential method (NEPM), the centroids of wavefunctions can be used to understand the increment in intrinsic gate capacitance with decreasing body thickness. Note that the simulated channel is p-type GeSn with [Sn] ranging from 0% to 20%. Our simulation also shows that nearly ideal subthreshold swing (SS) can be achieved by ultrathin body nanosheets (NSs). Thus, the concept of intrinsic areal gate capacitance proportional to channel peripheral width has to be modified in the ultrathin body channel.

The step-by-step strain evolution in the channel during the SiGe nanosheet (NS) integration process flow for pFETs is demonstrated using finite element analysis (FEA). The effect of device dimensions and defective source/drain (S/D) is studied. After fin formation, the 0.77% compressive biaxial strain resulting from the lattice mismatch between Si0.8Ge0.2 and Si substrate is observed. However, the strain $_{\textit {xx}}$ is gradually relaxed during the S/D recess and the inner spacer cavity formation. A large strain $_{\textit {xx}}$ is obtained on the channel along the current direction after Si0.6Ge0.4 S/D regrowth, increasing from 0.21% to 1.50% for defect-free S/D epitaxy. The compressive strain along the channel remains similar for different shapes of the S/D regrowth, with small variations between every channel. Decreasing the NS width only leads to an insignificant increase in channel strain $_{\textit {xx}}$ until the nanowire structure is formed. Nevertheless, the scaled body thickness can enhance the channel strainxx substantially with the 21.2% compressive strain $_{\textit {xx}}$ increase from ${t}_{\text {body}}$ = 5 nm to ${t}_{\text {body}}$ = 1 nm. The defective S/D is also simulated with air gaps between the merged epitaxes, where compressive strain in the channel is totally relaxed and further turns into tensile-strained. The hole mobility is expected to have a $3.6\times $ enhancement with 1.5% compressive strain $_{\textit {xx}}$ .

The topic of dry granular flow in the field of geological hazards has attracted considerable attention from the scientific community. Nevertheless, the motion and deposit characteristics of dry granular flow have not been well elucidated. In this study, an experimental model of dry granular flow was developed to investigate the influence of factors on the motion and deposit characteristics. Additionally, the shape of deposit continuum was emphatically discussed. The results demonstrate that: (1) the fine-particle group exhibits favorable continuity and integrity throughout the sliding process, while conversely, the coarse-particle group displays a higher degree of dispersion during the same process. (2) The dimensions of the resulting deposit, including its length, width, and thickness, are noticeably impacted by factors such as particle gradation, mass of the dry granular flow, length of the landslide, and slope angle. (3) Furthermore, an approximation of the leading-edge portion of the deposit continuum reveals a quadratic function image. The research findings indicate that an increase in slope angle leads to a reduction in the opening of the edge shape exhibited by the deposit continuum.

Data mining, integration, and utilization are the inevitable trend of the Internet of Medical Things (IoMT) in the context of Big Data. With the increasing demand for data privacy, federated learning has emerged as a new paradigm, which enables distributed joint training of medical data sources without leaving the private domain. However, federated learning is suffering from security threats as the shared local model will reveal original datasets. Privacy leakage is even more fatal in healthcare because medical data contains critically sensitive information. In addition, open wireless channels are susceptible to malicious attacks. To further safeguard the privacy of IoMT, we propose a comprehensive privacy-preserving federated learning scheme with a tactful dropout handling mechanism. The proposed scheme leverages blind masking and certificateless proxy re-encryption (CL-PRE) for secure aggregation, ensuring the confidentiality of the local model and rendering the global model invisible to any parties other than clients. It also provides authentication of uploaded models while protecting identity privacy. Compared with other relevant schemes, our solution has better performance on functional features and efficiency, and is more applicable to IoMT systems with many devices.

Electrode diffusion barrier plays an important role in thermoelectric cooling devices. Compared with p-type Bi0.5Sb1.5Te3, the compatibility between commercial Ni barrier and n-type Bi2Te2.7Se0.3is a key bottleneck to enhance the performance of Bi2Te3-based cooling devices. This paper proposed a NiP alloy barrier to improve the compatibility with n-type Bi2Te2.7Se0.3, and systemically investigated the contact and interfacial dynamics properties. Due to the low diffusion rate of NiP alloy, the initial interfacial contact resistivity of Bi2Te2.7Se0.3/NiP is as low as 0.90 μΩ cm2, and it further can be depressed below 1.98 μΩ cm2even after aging at 423 K for 35 days, indicating the superior thermal stability of the NiP barrier layer compared to the commercial Ni barrier layer. Based on the NiP barrier, a 15-pair bismuth telluride device is prepared and a high cooling temperature difference of 71.5 K at a hot-side temperature of 304 K is achieved, which proves the practical applications potential of NiP barrier for Bi2Te3-based modules.

Liver fibrosis is a wound-healing process characterized by excess formation of extracellular matrix (ECM) from activated hepatic stellate cells (HSCs). Previous studies show that both EZH2, an epigenetic regulator that catalyzes lysine 27 trimethylation on histone 3 (H3K27me3), and long non-coding RNA H19 are highly correlated with fibrogenesis. In the current study, we investigated the underlying mechanisms. Various models of liver fibrosis including Mdr2−/−, bile duct ligation (BDL) and CCl4mice were adapted. We found that EZH2 was markedly upregulated and correlated with H19 and fibrotic markers expression in these models. Administration of EZH2 inhibitor 3-DZNeP caused significant protective effects in these models. Furthermore, treatment with 3-DZNeP or GSK126 significantly inhibited primary HSC activation and proliferation in TGF-β-treated HSCs and H19-overexpreesing LX2 cells in vivo. Using RNA-pull down assay combined with RNA immunoprecipitation, we demonstrated that H19 could directly bind to EZH2. Integrated analysis of RNA-sequencing (RNA-seq) and chromatin immunoprecipitation sequencing (ChIP-seq) further revealed that H19 regulated the reprogramming of EZH2-mediated H3K27me3 profiles, which epigenetically promoted several pathways favoring HSCs activation and proliferation, including epithelial-mesenchymal transition and Wnt/β-catenin signaling. In conclusion, highly expressed H19 in chronic liver diseases promotes fibrogenesis by reprogramming EZH2-mediated epigenetic regulation of HSCs activation. Targeting the H19-EZH2 interaction may serve as a novel therapeutic approach for liver fibrosis.

Iron is indispensable for almost all forms of life but toxic at elevated levels1–4. To survive within their hosts, bacterial pathogens have evolved iron uptake, storage and detoxification strategies to maintain iron homeostasis1,5,6. Recent studies showed that three Gram-negative environmental anaerobes produce iron-containing ferrosome granules7,8. However, it remains unclear whether ferrosomes are generated exclusively by Gram-negative bacteria. The Gram-positive bacterium Clostridioides difficileis the leading cause of nosocomial and antibiotic-associated infections in the USA9. Here we report that C. difficileundergoes an intracellular iron biomineralization process and stores iron in membrane-bound ferrosome organelles containing non-crystalline iron phosphate biominerals. We found that a membrane protein (FezA) and a P1B6-ATPase transporter (FezB), repressed by both iron and the ferric uptake regulator Fur, are required for ferrosome formation and play an important role in iron homeostasis during transition from iron deficiency to excess. Additionally, ferrosomes are often localized adjacent to cellular membranes as shown by cryo-electron tomography. Furthermore, using two mouse models of C. difficileinfection, we demonstrated that the ferrosome system is activated in the inflamed gut to combat calprotectin-mediated iron sequestration and is important for bacterial colonization and survival during C. difficileinfection.

As the features of electronics are miniaturized, the need for interfacial thermal coupling layers to enhance their thermal transfer efficiency and improve device performance becomes critical. Organic conjugated small molecules possess a unique combination of periodic crystal structures and conjugated units with π electrons, resulting in notable thermal conductivities and molecular structure orientation that facilitates directed heat transfer. Nevertheless, there is a noticeable gap in literatures regarding the thermal properties of organic conjugated small molecules and their potential applications in nanoscale thermal management. Herein, we report the fabrication of high-quality thin films of organic conjugated small molecules. The result reveals that the 2D organic conjugated small molecule thin films exhibit a high cross-plane thermal conductivity of 3.2 W/m K. The increased thermal conductivity is attributed to the well-organized lattice structure and existence of π-electrons induced by conjugated systems. The studied conjugated small molecules engage in π–π stacking interactions with carbon materials and efficiently exchange energy with electrons in metals, promoting rapid interfacial heat transfer. These molecules act as coupling layers, significantly enhancing thermal transfer efficiency between graphite-based thermal pads and copper heat sinks. This pioneering research represents the inaugural investigation of the thermal performance of conjugated organic small molecules. These findings highlight the potential of conjugated small molecules as thermal coupling layers, offering tunable combinations of desirable properties.

With the large-scale deployment of the Internet of Vehicles (IoV) and 5G technologies, it is inevitable to share data frequently for superior in-vehicle services. However, due to the dynamically changing and widely distributed Vehicular Ad-hoc Networks (VANETs), data sharing still faces challenges in security, efficiency, and reliability. In this paper, we propose a secure and reliable data-sharing scheme (SDSS) for edge-enabled IoV networks. It assigns multiple attribute authorities to alleviate the management burden and support a large attribute universe catering to the various services in IoV. To enhance efficiency and flexibility, edge computing is introduced for quickly responding to vehicles’ requests and assisting resource-constrained vehicle computation. And an online/offline mechanism is designed to further alleviate the computational pressure of sharing data online. In addition, we put forward a cooperative key generation approach to guarantee the security of users’ private keys. The security analysis proves that SDSS ensures resistance to collusion attacks and indistinguishability under chosen-ciphertext attacks (IND-CCA). Moreover, it can avoid the single point of failure and resist denial of service (DoS) attacks with the help of multiple distributed edge nodes. The experiment demonstrates SDSS is practicable for IoV data sharing.

Two-electron oxidations are ubiquitous and play a key role in the synthesis and catalysis. For transition metals and actinides, two-electron oxidation often takes place at a single-metal site. However, redox reactions at rare-earth metals have been limited to one-electron processes due to the lack of accessible oxidation states. Despite recent advancements in nontraditional oxidation state chemistry, the low stability of low-valent compounds and large disparity among different oxidation states prevented the implementation of two-electron processes at a single rare-earth metal center. Here we report two-electron oxidations at a cerium(II) center to yield cerium(IV) terminal oxo and imido complexes. A series of cerium(II–IV) complexes supported by a tripodal tris(amido)arene ligand were synthesized and characterized. Experimental and theoretical studies revealed that the cerium(II) complex is best described as a 4f2ion stabilized by δ-backdonation to the anchoring arene, while the cerium(IV) oxo and imido complexes exhibit multiple bonding characters. The accomplishment of two-electron oxidations at a single cerium center brings a new facet to molecular rare-earth metal chemistry.

Filled elastomer composites have gained significant attention due to their ability to undergo large-strain reversible deformations with minimal force. However, achieving the desired functionality, such as high thermal conductivity, often requires ultrahigh filler loadings (above 50%). Unfortunately, excessive filler loading compromises the softness and toughness of the composites due to the prevalence of trapped entanglements. To address this challenge, a simple solvent-thermal design strategy is reported to optimize the balance among Young’s modulus, stretchability, and toughness in highly filled elastomer composites. This is realized by the curled conformation formed by the disentangling of the excessively entangled polymer chains and by better mixing of the BN filler and the polymer matrix. The released trapped entanglement can effectively reduce the Young’s modulus (2.80 MPa) of the C-PDMS/60 wt % BN elastomer composites, and the strong unfolding and stretching ability of the curled conformation also endows it with excellent stretchability (∼492%), thus achieving high toughness (∼2.80 MJ m–3). Additionally, the better mixing ability allows the C-PDMS/60 wt % BN elastomer composites to be compounded with the high BN filler loading (60 wt %), thus achieving high thermal conductivity (1.65 W m–1K–1). The comprehensive performance of the C-PDMS/60 wt % BN demonstrates remarkable advancements in highly filled elastomer composites. Leveraging these favorable characteristics, the curled PDMS/BN elastomer composites can serve as effective thermal interface materials for efficient heat dissipation and hold great potential for applications in the field of flexible electronics.

Obesity contributes to the progression of various chronic diseases, and shortens life expectancy. With abundant mitochondria, brown adipose tissue (BAT) dissipates energy through heat to limit weight gain and metabolic dysfunction in obesity. Our previous studies have shown that aurantio-obtusin (AO), a bioactive ingredient in Chinese traditional medicine Cassiae semensignificantly improves hepatic lipid metabolism in a steatotic mouse model. In the current study we investigated the effects of AO on lipid metabolism in the BAT of diet-induced obesity mice and in oleic acid and palmitic acid (OAPA)-stimulated primary mature BAT adipocytes. Obese mice were established by feeding a HFHS diet for 4 weeks, and then administered AO (10 mg/kg, i.g.) for another 4 weeks. We showed that AO administration significantly increased the weight of BAT and accelerated energy expenditure to protect the weight increase in the obese mice. Using RNA sequencing and molecular biology analysis we found that AO significantly enhanced mitochondrial metabolism and UCP1 expression by activating PPARα both in vivo and in vitro in the primary BAT adipocytes. Interestingly, AO administration did not improve metabolic dysfunction in the liver and white adipose tissue of obese mice after interscapular BAT excision. We demonstrated that low temperature, a trigger of BAT thermogenesis, was not a decisive factor for AO to stimulate the growth and activation of BATs. This study uncovers a regulatory network of AO in activating BAT-dependent lipid consumption and brings up a new avenue for the pharmaceutical intervention in obesity and related comorbidities.

Thermal resistance at a soft/hard material interface plays an undisputed role in the development of electronic packaging, sensors, and medicine. Adhesion energy and phonon spectra match are two crucial parameters in determining the interfacial thermal resistance (ITR), but it is difficult to simultaneously achieve these two parameters in one system to reduce the ITR at the soft/hard material interface. Here, we report a design of an elastomer composite consisting of a polyurethane–thioctic acid copolymer and microscale spherical aluminum, which exhibits both high phonon spectra match and high adhesion energy (>1000 J/m2) with hard materials, thus leading to a low ITR of 0.03 mm2·K/W. We further develop a quantitative physically based model connecting the adhesion energy and ITR, revealing the key role the adhesion energy plays. This work serves to engineer the ITR at the soft/hard material interface from the aspect of adhesion energy, which will prompt a paradigm shift in the development of interface science.