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Cytokinesis is required for faithful division of cytoplasmic components and duplicated nuclei into two daughter cells. Midbody, a protein-dense organelle that forms at the intercellular bridge, is indispensable for successful cytokinesis. However, the regulatory mechanism of cytokinesis at the midbody still remains elusive. Here, we unveil a critical role for NudC-like protein 2 (NudCL2), a co-chaperone of heat shock protein 90 (Hsp90), in cytokinesis regulation by stabilizing regulator of chromosome condensation 2 (RCC2) at the midbody in mammalian cells. NudCL2 localizes at the midbody, and its downregulation results in cytokinesis failure, multinucleation, and midbody disorganization. Using iTRAQ-based quantitative proteomic analysis, we find that RCC2 levels are decreased in NudCL2 knockout (KO) cells. Moreover, Hsp90 forms a complex with NudCL2 to stabilize RCC2, which is essential for cytokinesis. RCC2 depletion mirrors phenotypes observed in NudCL2-downregulated cells. Importantly, ectopic expression of RCC2 rescues the cytokinesis defects induced by NudCL2 deletion, but not vice versa. Together, our data reveal the significance of the NudCL2/Hsp90/RCC2 pathway in cytokinesis at the midbody. [ABSTRACT FROM AUTHOR]

Raising the cutoff voltage can efficiently increase the energy density of lithium cobalt oxide (LCO). However, upon charging over 4.55 V the LCO undergoes irreversible phase transition from the pristine O3 phase to the metastable H1‐3 phases, causing serious side reactions, which results in poor cycling stability. Herein, a multifunctional aqueous composite binder derived from the cross‐linking of fucoidan (FUC) and polyacrylamide (PAM) is developed to enhance the stability of LCO cathode at 4.6 V. The cross‐linking interaction of FUC and PAM provides a uniform coating on the surface of LCO and ensures a high peel strength for the electrode, effectively mitigating irreversible phase transition and detrimental interface side reactions. More importantly, the sulfur ester and amide groups of FUC‐PAM favorably function as surface charge compensators to the high valent Co upon charging under high voltages, thus stabilizes the surface lattice of LCO and suppresses the detrimental oxygen release. As expected, the LCO with a cutoff voltage of 4.6 V exhibits a high capacity retention of 90% after 100 cycles at a current density of 110 mA g−1. The interfacial coordination effect of composite binders offers a novel strategy to enhance the stability of high‐voltage LCO for high‐energy lithium‐ion batteries. [ABSTRACT FROM AUTHOR]

The safe operation of closed-Bryton-cycle system is hindered by the nonlinear real gas properties in a supercritical carbon dioxide (SCO2) centrifugal compressor for waste heat recovery in a powertrain system. This paper aims to understand the influence of real gas properties on the aerodynamic stability of a shrouded SCO2 centrifugal compressor designed for waste heat recovery. Firstly, the numerical method was calibrated and validated using experimental results from the Sandia SCO2 centrifugal compressor. Next, based on the numerical method, the stability performance of an inhouse-design shrouded SCO2 compressor was discussed through a direct comparison with the identical compressor using air. The results showed that the performance of the SCO2 compressor was significantly different from that of the air compressor. Particularly, the impeller was the most unstable component featuring a notable recirculating region near the shroud at the leading edge. Further analysis is carried out to understand the discrepancies in the stability performance between the two compressors with different fluids. It is revealed that the boundary layer on the SCO2 impeller suction surface thickens at a faster rate, leading to stronger flow separation. Meanwhile, the stronger accumulation of low-momentum secondary flow near the SCO2 impeller outlet enhances the 'wake' structure near the shroud of suction surface at the impeller tailing edge, resulting in considerable backflow. The different behaviors of boundary layer were attributed to pressure gradient normal to the suction surface. Specifically, the pressure gradient on the suction surface for SCO2 impeller is orders of magnitude higher than that of the air impeller. The stronger gradient weakens momentum exchange in the boundary layer, thus increasing the thickness of boundary layer more rapidly along the streamwise direction. Moreover, the boundary layer is pushed towards the shroud of suction surface by the strong pressure gradient, resulting in the evident accumulation of secondary flow nearby. At the meantime, the low-momentum flow near the impeller outlet reduced the inlet flow velocity of the diffuser, causing more recirculation at the top of the vaneless diffuser in all circumferential directions, thus worsening its instability. [ABSTRACT FROM AUTHOR]

The bandgap modulation and electronic properties modulation of two-dimensional HfSi2N4 monolayer induced by strain, electric field and atomic adsorption are studied by first principles. The HfSi2N4 monolayer was found to be dynamically, thermally, and mechanically stable at equilibrium, and it is a direct semiconductor with a bandgap of 1.87 eV. The bandgap of the HfSi2N4 monolayer can be precisely modulated by strain. Under the action of strain, HfSi2N4 monolayer not only transforms from direct semiconductor to indirect semiconductor, but also improves the absorption of visible light. An external electric field in the 0–0.5 eV/Å range can also modulate the bandgap of HfSi2N4 monolayer from 1.87 eV to 0 eV, and most importantly, at an external electric field of 0.5 eV/Å, HfSi2N4 monolayer shows the characteristics of spin gapless semiconductor. The calculated adsorption energy shows that the structures of H, O and F atoms adsorbed by HfSi2N4 monolayer can all exist stably. The bandgap of the configuration after adsorption of O and F atoms is significantly reduced compared with that of HfSi2N4 monolayer. Furthermore, the HfSi2N4 monolayer after adsorption of H and F atoms is transformed into a magnetic semiconductor. Method: All calculations were performed using Vienna ab initial simulation package, The electronic structure, mechanical properties, electronic properties and other properties were carried out using generalized gradient approximation (GGA-PBE), supplemented by HSE06 and GGA + U. The total-energy and force convergence are less than 10–6 eV and 0.001 eV/Å, respectively. The vacuum on the z-axis is selected 20 Å. The vdW interactions were corrected using the Grimme scheme (DFT-D3). [ABSTRACT FROM AUTHOR]

In the era of the digital society, information has experienced rapid development, and individuals, including the elderly, are increasingly relying on various media to access the information they require. However, there has been limited research on how media usage as a behavior influences the subjective perceptions of older adults and the motivating factors driving their use of media in the digital age. Drawing on the activity theory and knowledge-gap theory, this study aims to investigate whether media use mediates the connection between social participation and subjective well-being among older adults in China. The study also pays specific attention to potential intergroup differences, such as age-group relationships and the types of media involved. We selected a nationally representative sample comprising 938 older adults aged 60 and above from the 2021 Chinese General Social Survey and incorporated them into the mediation analysis. Structural equation modeling (SEM) with path analysis and maximum likelihood procedures was used to analyze the data. Our findings revealed a positive association between social participation and media use, as well as a positive association between media use and subjective well-being. The path analysis further demonstrated that media use mediated the relationship between social participation and subjective well-being. Specifically, social participation through media use, acting as a mediating variable, accounting for 75.3% of the influence on subjective well-being. Distinct age groups exhibited significantly varied levels of social participation, with traditional media (paper-based) playing a more substantial role in our model compared to electronic media (such as television, radio, internet, social media, and mobile applications). The results suggest that older adults with a higher frequency of social participation exhibit stronger levels of media use, and high levels of media use are associated with elevated levels of subjective well-being. The results of this study highlight the positive indirect effects of social participation, media use, and subjective well-being, emphasizing the intricate interplay between these factors among older adults in China. [ABSTRACT FROM AUTHOR]

In order to optimize the design of the tool edge, an intelligent method was used for modeling and optimization. The tool edge design method based on support vector regression (SVR) and particle swarm optimization (PSO) was proposed. By combining tool edge parameters and processing condition parameters, and learning from empirical data, a functional model was established between tool life and edge parameters and processing condition parameters. Taking the tool life as the objective function, the optimal edge profile design parameters were solved under different processing condition parameters. The T-shape tool was taken as a case for verification. The SVR-PSO function model was established and solved based on the processing condition parameters, and the optimized edge design parameters and predicted tool life were obtained. The results showed that the deviation between the calculated and actual tool life was less than 6.4%. This method was feasible and practical and has been applied in the design department of tool manufacturing companies. [ABSTRACT FROM AUTHOR]

Silicon nitride (Si3N4) has great potential for applications in photoelectric and semiconductor fields. In this study, a novel strategy of fabricating Si3N4 crystals is reported, and the morphology of α-Si3N4 can be controlled. The aBN/SiO2/Si wafers were designed and irradiated by a high-energy electron beam for 2 min using home-made equipment. Tree-like α-Si3N4 dendrites and [001]-oriented unbranched α-Si3N4 whiskers can be synthesized by controlling the electron beam energy. Related formation mechanisms were analyzed based on componential and structural characterization using a scanning electron microscope and high-resolution transmission electron microscope. In addition, photoluminescence measurements indicate that the synthesized α-Si3N4 exhibit unique photoluminescence properties. This is attributed to α-Si3N4 forming abundant Si–Si bonds, Si dangling bonds, N dangling bonds and oxygen bonds in the synthesis process. These findings provide new insights into fabricating high-quality Si3N4 crystals, as well as developing related high-performance micro- or nano-devices. [ABSTRACT FROM AUTHOR]

Turbochargers whose turbines contain two-entry volutes are advantageous as they help to improve the low-end torque and transient performance of internal combustion engines. Two types of two-entry turbines are applied currently in turbocharging, which are the twin-entry turbine (TE) and the double-entry turbine (DE). To develop more efficient turbocharged engines, a further understanding of the performance characteristics and loss mechanisms of two types of two-entry turbines is needed. However, few investigations have been carried out to directly compare these two types of turbines. Through an experimentally validated numerical method, this paper compares the performance and detailed flow mechanism of twin/double-entry turbines with the same nozzled mixed-flow rotor. The 3D simulation is validated against the measured performance as well as the flow field carried out on test rigs. Results show that the performance of the double-entry turbine is notably superior over that of the twin-entry counterpart although their peak swallowing capacities and efficiencies are at a similar level. In particular, the efficiency and swallowing capacity deteriorate more gently for the double-entry turbine as operational condition deviates from full admission. It was revealed via the loss breakdown of turbine components that, the volute and the nozzle are the main contributors to the performance discrepancy between the two turbines. Specifically, the loss in the twin-entry volute is higher than that of the double-entry one, especially in the case of partial admissions. Flow analysis shows that the flow is mixed strongly in the vicinity of the limb divider of the twin-entry volute in the whole circumference, while it only concentrates in the vicinity of the tongues for the double-entry turbine. Therefore, a higher entropy-rise is generated in the twin-entry volute. Moreover, the mixing flow attenuates the flow distortion in the nozzle and produces more uniform entropy rise in the nozzle for the twin-entry configuration. On the other hand, flow distortion is well preserved in nozzle for the double-entry turbine, thus regions with high entropy-rise appear in a portion of nozzle passages. Consequently, a higher loss is produced in the volute and the nozzle for the twin-entry turbine. This paper provides knowledge of performance characteristics of two two-entry turbines and sheds light on the performance improvement of two-entry turbines. [ABSTRACT FROM AUTHOR]

To address the problem that complex bearing faults are coupled to each other, and the difficulty of diagnosis increases, an improved envelope spectrum–maximum second-order cyclostationary blind deconvolution (IES-CYCBD) method is proposed to realize the separation of vibration signal fault features. The improved envelope spectrum (IES) is obtained by integrating the part of the frequency axis containing resonance bands in the cyclic spectral coherence function. The resonant bands corresponding to different fault types are accurately located, and the IES with more prominent target characteristic frequency components are separated. Then, a simulation is carried out to prove the ability of this method, which can accurately separate and diagnose fault types under high noise and compound fault conditions. Finally, a compound bearing fault experiment with inner and outer ring faults is designed, and the inner and outer ring fault characteristics are successfully separated by the proposed IES-CYCBD method. Therefore, simulation and experiments demonstrate the strong capability of the proposed method for complex fault separation and diagnosis. [ABSTRACT FROM AUTHOR]

With the advantages of high efficiency and compact structure, supercritical carbon dioxide (sCO2) Brayton cycles have bright prospects for development in energy conversion field. As one of the core components of the power cycle, the centrifugal compressor tends to operate near the critical point (304.13 K, 7.3773 MPa). Normally, the compressor efficiency increases as the inlet temperature decreases. When the inlet temperature is close to the critical point, the density increases sharply as the temperature decreases, which results in quickly decreasing of volume flow rate and efficiency reducing. The flow loss mechanism of the sCO2 compressor operating at low flow rate is studied in this paper. Computational fluid dynamics (CFD) simulations for sCO2 compressor were carried out at various inlet temperatures and various mass flow rates. When the sCO2 compressor operates at low volume flow rate, the flow loss is generated mainly on the suction side near the trailing edge of the blade. The flow loss is related to the counterclockwise vortexes generated on the suction side of the main blade. The vortexes are caused by the flow separation in the downstream region of the impeller passage, which is different from air compressors operating at low flow rates. The reason for this flow separation is that the effect of Coriolis force is especially severe for the sCO2 fluid, compared to the viscous force and inertial force. At lower flow rates, with the stronger effect of Coriolis force, the direction of relative flow velocity deviates from the direction of radius, resulting in its lower radial component. The lower radial relative flow velocity leads to severe flow separation on the suction side near the trailing edge of the main blade. [ABSTRACT FROM AUTHOR]

Electronic paper (e‐paper) is a reflective display technology with unique advantages, such as bistability, low‐power consumption, and high ambient contrast ratio. These features make e‐paper a promising candidate for future Internet of Things applications. Among different technologies of e‐paper, electrophoretic display (EPD) is the most successful one for commercialization. However, the edge ghosting (also known as the fringing effect) still limits the performance of EPD. Herein, we established a model of particle dynamics of electrophoresis, simulated the edge ghosting of microcapsule EPD, analyzed the edge ghosting effect, and revealed the relationship between thicknesses, dielectric constants of the back binder layer, and the edge ghosting. Two EPD panels with different thicknesses of back binder layer were demonstrated, which verifies the accuracy of this simulation model. With the proposed model, many device mechanisms and product issues can be analyzed and illustrated, which is supposed to guide the researchers in optimizing the device structure design of EPD. [ABSTRACT FROM AUTHOR]

Understanding the response of performance of two-stage turbine to pulsating flow in exhaust manifold system is essential for performance improvement of engine. This paper studies unsteady interaction of two turbines in a two-stage turbocharging system via experimental method and a reduced order model. Firstly, experimental results of the unsteady pressure ratio of two turbines are discussed in cases with different engine speeds, engine loads, and bypass valve openings. Results show that the pressure ratio distribution between two turbines is profoundly influenced by the engine condition. The pressure ratio of low-pressure turbine (LPT) increases consistently with the engine speed and load, while it increases slightly or even remains unchanged for high-pressure turbine (HPT). HPT is de-loaded when the bypass valve is open, and there are large numbers of fluctuations with high frequencies in the trace of pressure ratio when the bypass valve is open. Next, a reduced order model of the two-stage turbine is established for turbine responses at pulsating conditions, and model validations of performance and unsteady pressure in two-stage turbine all show high precision. Finally, the model is applied for performance analysis of two-stage turbine system under pulsating conditions. The results show that with the increase in engine speed, load or bypass valve opening, the hysteresis loops of both turbines are expanded around the steady performance curve. However, the deviation of cycle-average performance from steady case for two turbines is notably different. LPT shows a stronger throttling effect at pulsating inflows. Moreover, compared with steady performance for whole two-stage turbine, cycle-average performance is reduced for all pulsating cases, especially for cases of open valve. The differences in turbine performance of two-stage turbine system caused by gasdynamic coupling effect of two turbines are suggested to be considered in the turbo-engine matching. [ABSTRACT FROM AUTHOR]

Injecting CO2 into tight oil reservoirs is a potential approach for enhanced oil recovery (EOR) and CO2 sequestration. However, the effects of different pore-scales on EOR are poorly understood, and this has a significant impact on recovery. In this paper, a pore size correction model based on X-ray computerized tomography (CT) and nuclear magnetic resonance (NMR) was developed in order to establish the relationship between the pore radius and the transverse relaxation time. Different pore-scales are divided according to the cumulative distribution characteristics of the transverse relaxation time (T2). CO2 flooding and huff-n-puff experiments were conducted to investigate the dynamic displacement behaviors in different pore-scales. The results indicate that there are three pore-scales: micropores (T2 < 0.3 ms), intermediate pores (0.3 ms < T2 < 100 ms), and macropores (100 ms < T2). However, there are also pseudo-sweep pores (PPs), equilibrium pores (EPs), and sweep pores (SPs) in the intermediate pores, depending on whether crude oil has been produced. Interestingly, the pressurization process causes some crude oil in the large pores to be squeezed into small pores. The recovery of CO2 huff-n-puff (19.75%) is obviously lower than that of CO2 flooding (51.61%). Specifically, it was observed that the micropores (−8%) and the pseudo-sweep pores (−37%) have a negative impact on oil recovery, whereas all pore-scales exhibit positive effects during CO2 flooding. In addition, it was found that the critical pore radiuses of CO2 flooding and huff-n-puff were 2.61 ms (0.15 µm) and 25 ms (1.5 µm), respectively, in the experiments, and that there is also more oil remaining in the macropores and the sweep pores during CO2 huff-n-puff. These results provide a deeper understanding of the displacement behaviors of different pore-scales in tight oil reservoirs. [ABSTRACT FROM AUTHOR]

The mitigation of water flooding in the gas diffusion layer (GDL) at relatively high current densities is indispensable for enhancing the performance of proton exchange membrane fuel cells (PEMFCs). In this paper, a 2D multicomponent LBM model is developed to investigate the effects of porosity distribution and compression on the liquid water dynamic behaviors and distribution. The results suggest that adopting the gradient GDL structure with increasing porosity along the thickness direction significantly reduces the breakthrough time and steady–state total water saturation inside the GDL. Moreover, the positive gradient structure reaches the highest breakthrough time and water saturation at 10% compression ratio (CR) when the GDL is compressed, and the corresponding values decrease with further increase of the CR. Considering the breakthrough time, total water saturation and water distribution at the entrance of the GDL at the same time, the gradient structure with continuously increasing porosity can perform better water management capacity at 30% CR. This paper is useful for understanding the two–phase process in a gradient GDL structure and provides guidance for future design and manufacturing. [ABSTRACT FROM AUTHOR]

Lipoprotein(a) (Lp[a]) is a particle consisting of a low‐density lipoprotein (LDL)‐like core connected to an apolipoprotein(a) chain, which is an established risk factor for cardiovascular disease. However, studies addressing the relationship between atrial fibrillation (AF) and Lp(a) demonstrated conflicted results. Thus, we sought to evaluate this relationship by conducting this systemic review and meta‐analysis. We performed a comprehensive systematic search of health science databases, including PubMed, Embase, Cochrane Library, Web of Science, MEDLINE, and ScienceDirect, to identify all relevant literature from their inception to March 1, 2023. We identified nine related articles, which were eventually included in this study. Our study showed no association between Lp(a) with new‐onset AF (HR = 1.45, 95% confidence interval [CI]: 0.57–3.67, p =.432). In addition, genetically elevated Lp(a) was not associated with the risk of atrial fibrillation (OR = 1.00, 95% CI: 1.00–1.00, p =.461). Different stratification of Lp(a) levels may have different outcomes. Also, higher Lp(a) levels may be inversely associated with the risk of developing AF compared to those with lower levels. Lp(a) levels were not associated with incident AF. Further research is needed to identify the mechanism underlying these results and better understand Lp(a) stratification for AF and the possible inverse association between Lp(a) and AF. [ABSTRACT FROM AUTHOR]

As an ultra-wide bandgap semiconductor, hexagonal boron nitride (h-BN) has drawn great attention in solar-blind photodetection owing to its wide bandgap and high thermal conductivity. In this work, a metal-semiconductor-metal structural two-dimensional h-BN photodetector was fabricated by using mechanically exfoliated h-BN flakes. The device achieved an ultra-low dark current (16.4 fA), high rejection ratio (R 205nm/ R 280nm = 235) and high detectivity up to 1.28 × 1011 Jones at room temperature. Moreover, due to the wide bandgap and high thermal conductivity, the h-BN photodetector showed good thermal stability up to 300 °C, which is hard to realize for common semiconductor materials. The high detectivity and thermal stability of h-BN photodetector in this work showed the potential applications of h-BN photodetectors working in solar-blind region at high temperature. [ABSTRACT FROM AUTHOR]

Cesium lead halide perovskite nanocrystals (PNCs) have attracted great attention in optoelectronic devices due to their excellent optical properties, such as tunable emission wavelengths, long carrier lifetime, and narrow full width at half-maximum (fwhm). However, the poor stability of PNCs in water or humid environments greatly limits their wide-spreading applications. It is challenging to prepare PNCs with long-term stability in water. Herein, we successfully prepared CsPbBr3@PDMS microspheres by using the emulsification method. Due to the protection of the PDMS layer, the CsPbBr3@PDMS microspheres exhibit good optical properties and stability in water, acid, and alkali solutions. In addition, to expand the application of CsPbBr3 NCs in flexible optical devices and wearable devices, we first prepared stretchable, stable, and photoluminescent hydrogel with a CsPbBr3@PDMS microsphere (hydrogel/CsPbBr3@PDMS) by using the emulsification method. The hydrogel/CsPbBr3@PDMS elastomer exhibits good stability and stretchability. Furthermore, the hydrogel/CsPbBr3@PDMS elastomer retains bright green emission and stability under different mechanical deformations. This work provides a method to improve the CsPbBr3 PNCs with high stability by emulsification, which could also expand the applications of PNCs in underwater display, wearable, and flexible optoelectronic devices. [ABSTRACT FROM AUTHOR]

With the development of carbon-based electronics, the polycrystalline diamond has drawn much attention in diamond electronic devices; as compared to single crystalline diamond, the scale of the polycrystalline diamond can be fabricated over 4 in. much more easily. However, until now, the influence factors on the surface conductivity of hydrogen-terminated polycrystalline diamond (H-PCD) are still unclear. In this work, the carrier concentration and mobility of H-PCD were investigated through Hall effect measurement. It was found that besides surface roughness, the temperature at which the equilibrium states of adsorption and desorption of H-PCD surface adsorbates are established also plays an important role in carrier concentration and mobility. With the increase of the establishment temperature, both carrier concentration and mobility show a decreasing tendency, which may be determined by the coefficient of the surface ionic scattering, phonon scattering, and the grain boundaries on the H-PCD surface. The investigation of this work will give some insight into the control of the surface conductivity on H-PCD from the aspect of the equilibrium state established temperature and surface roughness. [ABSTRACT FROM AUTHOR]

The chelating ligands of boric acid and amino trimethyl phosphonate prepared a novel flame retardant (BAP) for the cotton fabric. A stable chemical and coordination bond was formed on the surface of the cotton fibers by a simple three‐curing finishing process to make the fabric exhibits excellent durable flame retardancy. Cotton fabrics' tensile strength and whiteness got substantially retained after BAP treatment. 90 g/L BAP‐treated samples (3 curing times, 50 laundry cycles) showed good flame retardancy and durability, holding the largest limit oxygen index, 29.7%, and the shortest damage length, 61 mm. A condensed phase and gas phase synergistic flame retardant mechanism was concluded by thermogravimetric, cone calorimeter tests, and thermogravimetric infrared analysis. [ABSTRACT FROM AUTHOR]

A highly stable new structural phase of monoelemental two-dimensional boron sheet has been discovered. Such new material was acquired by removing the metal atom layers from the quasi-layered boride material AlMgB14, inspired by the top-down synthesis of MXenes, which includes the direct etching and exfoliation of the bulk MAX phase. It has been shown that this structure possesses distinct stability over other two-dimensional boron phases, which is caused by the B–B single bonds that connect B12 clusters and three-coordinate boron atoms, instead of the universally existing three-center two-electron B–B bonds. This new structure has proved to be a direct narrow bandgap semiconductor with intermediate bands and favorable for metal cation and hydrogen molecule adsorption. Specifically, this new structure exhibits particularly high specific capacities as anodes for various metal ion batteries. The findings indicate that this new structure of two-dimensional boron has great potential in the energy fields, such as high-efficiency solar cells, energy storage devices and hydrogen storage substrates. [ABSTRACT FROM AUTHOR]

Highlights: A three-tiered thermal interface materials was proposed with the through-plane thermal conductivity up to176 W m−1 K−1 and contact thermal resistance as low as 4–6 K mm2 W−1 (double sides). The liquid metal acts as a buffer layer to connect vertically aligned graphene with the rough heater/heat sink, improving effective contact thermal conductance by more than an order of magnitude. Developing advanced thermal interface materials (TIMs) to bridge heat-generating chip and heat sink for constructing an efficient heat transfer interface is the key technology to solve the thermal management issue of high-power semiconductor devices. Based on the ultra-high basal-plane thermal conductivity, graphene is an ideal candidate for preparing high-performance TIMs, preferably to form a vertically aligned structure so that the basal-plane of graphene is consistent with the heat transfer direction of TIM. However, the actual interfacial heat transfer efficiency of currently reported vertically aligned graphene TIMs is far from satisfactory. In addition to the fact that the thermal conductivity of the vertically aligned TIMs can be further improved, another critical factor is the limited actual contact area leading to relatively high contact thermal resistance (20–30 K mm2 W−1) of the "solid–solid" mating interface formed by the vertical graphene and the rough chip/heat sink. To solve this common problem faced by vertically aligned graphene, in this work, we combined mechanical orientation and surface modification strategy to construct a three-tiered TIM composed of mainly vertically aligned graphene in the middle and micrometer-thick liquid metal as a cap layer on upper and lower surfaces. Based on rational graphene orientation regulation in the middle tier, the resultant graphene-based TIM exhibited an ultra-high thermal conductivity of 176 W m−1 K−1. Additionally, we demonstrated that the liquid metal cap layer in contact with the chip/heat sink forms a "liquid–solid" mating interface, significantly increasing the effective heat transfer area and giving a low contact thermal conductivity of 4–6 K mm2 W−1 under packaging conditions. This finding provides valuable guidance for the design of high-performance TIMs based on two-dimensional materials and improves the possibility of their practical application in electronic thermal management. [ABSTRACT FROM AUTHOR]

Human–machine interaction will be revolutionarily different in the future Internet of Things (IoT) environments. Many displays will be adopted onto electronic devices to enhance human–device communication, even under a very bright sunlight ambience. Thus, power consumption and sunlight visibility are important attributes for this application. Electrophoretic displays (EPDs) have the inherent advantages of ultra‐low power consumption and high sunlight visibility, which are perfectly suitable for IoT applications. The low power consumption resulted from the balance of viscosity, gravity, and other complicated forces involved in the electrophoretic dispersion. This force balance is generally termed "bistability," meaning the particle‐packing can be stable without external power at black and white image states. However, good bistability implies a slow image updating rate, significantly degrades users' experience. In this work, a 3D network structure that undergoes disruption and reorganization with the particles' movement is utilized in the electrophoretic ink dispersion. Dynamic viscosity modulation enables the bistable and fast‐response dual‐working modes. The newly developed design can increase the response speed of EPDs by a factor of 2.38, simultaneously maintaining the bistability. The electronic ink with this reversible network provides a promising solution for the future video‐rate e‐paper displays. [ABSTRACT FROM AUTHOR]

In recent years, we have witnessed numerous indoor fires caused by the flammable properties of cotton. Flame-retardant cotton deserves our attention. A novel boric acid and diethylenetriaminepenta (methylene-phosphonic acid) (DTPMPA) ammonium salt-based chelating coordination flame retardant (BDA) was successfully prepared for cotton fabrics, and a related retardant mechanism with ion transfer was investigated. BDA can form a stable chemical and coordination bond on the surface of cotton fibers by a simple three-curing finishing process. The limiting oxygen index (LOI) value of BDA-90 increased to 36.1%, and the LOI value of cotton fabric became 30.3% after 50 laundering cycles (LCs) and exhibited excellent durable flame retardancy. Fourier-transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM) methods were used to observe the bonding mode and morphology of BDA on cotton fibers. A synergistic flame-retardant mechanism of condensed and gas phases was concluded from thermogravimetry (TG), cone calorimeter tests, and TG-FTIR. The test results of whiteness and tensile strength showed that the physical properties of BDA-treated cotton fabric were well maintained. [ABSTRACT FROM AUTHOR]

A model of particles dynamics of electrophoretic display was established to simulate the distribution of charged particles, edge ghosting effect with different thicknesses, dielectric constants of back binder layer. Reflectivities corresponding to particles distributions were simulated, which evaluated the extent of edge ghosting. The model can suggest the best values of the above parameters. [ABSTRACT FROM AUTHOR]

A model of particles dynamics of electrophoretic display was established to simulate the distribution of charged particles, edge ghosting effect with different thicknesses, dielectric constants of back binder layer. Reflectivities corresponding to particles distributions were simulated, which evaluated the extent of edge ghosting. The model can suggest the best values of the above parameters. [ABSTRACT FROM AUTHOR]

The terahertz stealth and shielding performance of a new type of two-dimensional material, borophene, has been studied theoretically and experimentally. Studies have shown that borophene materials have good terahertz stealth and shielding properties. First-principles calculations show that compared with single-layer borophene, few-layer borophene has good terahertz stealth and shielding performance in the range of 0.1~2.7 THz. In the range of 2~4 layers, the terahertz stealth and shielding performance of few-layer borophene increases with the increase of the number of layers. The finite element simulation calculation results also confirmed this point. Using the few-layer borophene prepared by our research group as a raw material, a PDMS composite was prepared to verify the terahertz stealth and shielding performance of the few-layer borophene. In the ultra-wide frequency range of 0.1~2.7 THz, the electromagnetic shielding effectiveness (EMI SE) of the PDMS material mixed with few-layer borophene can reach 50 dB, and the reflection loss (RL) can reach 35 dB. With the concentration of few-layer borophene increasing, the terahertz stealth and shielding effectiveness of the material is enhanced. In addition, the simultaneous mixing of few-layer borophene and few-layer graphene will make the material exhibit better terahertz stealth and shielding performance compared with mixing separately. [ABSTRACT FROM AUTHOR]

Tremendous advances in stretchable and biocompatible electronics have led to broad requirements of wearable display devices. However, most devices suffer from insufficient reliability owing to structural mismatch and bubbles under repeated deformation. To address this issue, this article presents a stretchable electrophoretic display (SEPD) with reinforced adhesion by in situ adhesion decoration between the hydrogel electrode and the elastomer display layer. The SEPD with a maximum strain of over 80% can still operate properly. Moreover, the SEPD device is endowed with stretchable, washable, rewritable, and erasable properties owing to the inherent characteristics of the elastomer‐based materials used. Arbitrary texts and patterns can be drawn and maintained for over 43 days of bistability without a predetermined patterned electrode or a thin‐film transistor as the addressing switches. In addition, the casting and blade coatings used in this work are suitable for mass production. The proposed hybrid structure with tough adhesion provides a new paradigm for other wearable devices. [ABSTRACT FROM AUTHOR]

Fourier ptychography imaging is a powerful phase retrieval method that can be used to realize super-resolution. In this study, we establish a mathematical model of long-distance camera scanning based on reflective Fourier ptychography imaging. In order to guarantee the effective recovery of a high-resolution image in the experiment, we analyze the influence of laser coherence in different modes and the surface properties of diverse materials for diffused targets. For the analysis, we choose a single-mode fiber laser as the illumination source and metal materials with high diffused reflectivity as the experimental targets to ensure the validity of the experimental results. Based on the above, we emulate camera scanning with a single camera attached to an X-Y translation stage, and an experimental system with a working distance of 3310 mm is used as an example to image a fifty-cent coin. We also perform speckle analysis for rough targets and calculate the average speckle size using a normalized autocorrelation function in different positions. The method of calculating the average speckle size for everyday objects provides the premise for subsequent research on image quality evaluation; meanwhile, the coherence of the light field and the targets with high reflectivity under this experiment provide an application direction for the further development of the technique, such as computer vision, surveillance and remote sensing. [ABSTRACT FROM AUTHOR]

Borophene has received much attention due to its unique structure and electronic properties. However, the application of borophene has been limited by the template effect of the growth metal substrate. A stable borophene/graphene (B/G) heterostructure is designed and prepared by the resonance ball milling method and one‐step molding strategy to realize the application of borophene in the lithium‐ion battery for the first time. Graphene serves as a supporting substrate for borophene, and the B/G anode has a better specific capacity and rate performance than the reduced graphene (G) oxide skeleton. By comparing the electrochemical performance of boron powder samples under different ball milling times, it is found that the anode of B/G heterostructure with 6 h boron powder has the largest specific capacity of 192.3 mAh g–1, which is 39% higher than that of the graphene framework. Oxidation functional groups on the surface of borophene are beneficial for the rate performance of the anode. And the influence of the surface functional groups of borophene are analyzed on the diffusion performance through the first principles. It is believed that the B/G has potential for further applications in the field of lithium‐ion batteries. [ABSTRACT FROM AUTHOR]

NLRP3 inflammasome is involved in the pathology of multiple human inflammatory diseases but there are still no clinically available medications targeting the NLRP3 inflammasome. We have previously identified RRx-001 as a highly selective and potent NLRP3 inhibitor, however, it contains high-energy nitro functional groups and may cause potential processing problems and generates highly toxic oxidants. Here, we show that compound 149-01, an RRx-001 analogue without high-energy nitro functional groups, is a potent, specific and covalent NLRP3 inhibitor. Mechanistically, 149-01 binds directly to cysteine 409 of NLRP3 to block the NEK7-NLRP3 interaction, thereby preventing NLRP3 inflammasome complex assembly and activation. Furthermore, treatment with 149-01 effectively alleviate the severity of several inflammatory diseases in mice, including lipopolysaccharide (LPS)-induced systemic inflammation, monosodium urate crystals (MSU)-induced peritonitis and experimental autoimmune encephalomyelitis (EAE). Thus, our results indicate that 149-01 is a potential lead for developing therapeutic agent for NLRP3-related inflammatory diseases. [ABSTRACT FROM AUTHOR]

Featured Application: The technology in the study has great prospects in remote sensing imaging. It was able to reconstruct the high-resolution intensity image and the phase information and realize the effect of synthetic aperture of one small aperture scan by using the low-resolution intensity images and improve the robustness of the system, as well as overcoming the difficulty of confocal and co-phase between multiple sub-apertures. Fourier ptychography (FP) is a powerful phase retrieval method that can be used to reconstruct missing high-frequency details and high-space-bandwidth products in microscopy. In this study, we further advanced the application of FP in microscopic imaging to the field of macroscopic far-field imaging, incorporating camera scanning for spatial resolution improvement. First, on the basis of the Fraunhofer diffraction mechanism and the transmission imaging model, we found the analysis of the associated theoretical fundamentals via simulations and experiments to be crucially relevant to the far-field of FP imaging. Second, we built an experimental device with long-distance imaging and experimentally demonstrated the relationship between the spectrum overlap ratio and the reconstructed high-resolution image. The simulation and experimental results showed that an overlap ratio higher than 50% had a good reconstruction effect. Third, camera scanning was used to obtain low-resolution intensity images in this study, for which the scanning range was wide and spherical wave illumination was satisfied, and therefore different positions corresponded to different aberrations of low-resolution intensity images, and even different positions of the same image had aberration differences, leading to inconsistencies in the aberrations of different images. Therefore, in the reconstruction process, we further overcame the effect of the inconsistency of aberrations of different images using the partition reconstruction method, which involves cutting the image into smaller parts for reconstruction. Finally, with the proposed partition reconstruction algorithm, we were able to resolve 40 μm line width of GBA1 resolution object and obtain a spatial resolution gain of 4× with a working distance of 2 m. [ABSTRACT FROM AUTHOR]

Flexible liquid crystal displays (LCDs) are regarded as one of the most promising candidates to achieve flexible displays. In this paper, we proposed a novel technique to fabricate flexible LCDs combining polymer walls (PWs) and self‐assembled‐monolayer(SAM). The PWs with fine morphology and line‐width (about 20 µm) were fabricated to keep uniform cell gap and provided a larger aperture opening ratio for flexible LCDs. Alignment by alkyl trichlorosilane(TS) SAM was achieved at room temperature. In this way, general flexible substrates could be used for flexible LCDs. This work is promising for the manufacture of flexible LCDs. [ABSTRACT FROM AUTHOR]

This research aims to propose a method to achieve the maximum altitude adaptability of turbocharged diesel engines with the optimum fuel consumption. Firstly, engine performance at different altitudes is studied by experimental method. It is found that the engine power recovery is restricted by three constraints, which are cylinder pressure, exhaust temperature and boosting pressure ratio. Following that, the influence of turbocharging system and fuel injection on the three constraints is studied via experimentally validated numerical model. A power-recovery-zone bounded by the three constraints is proposed, inside which engine power can be fully recovered. The altitude adaptability of the engine is discussed in details via this zone. Further analysis finds that the boosting pressure and the maximum pressure ratio are the key factors to the constraints. A new methodology which can achieve the maximum altitude with the optimum fuel consumption is proposed based the concept of the zone. Finally, the methodology is applied in the engine with three types of turbocharging systems to quantitatively compare their altitude adaptability. Results prove that the altitude adaptability of the engine is notably improved by adapting the proposed method, especially for the two stage turbocharging system. [ABSTRACT FROM AUTHOR]

Purpose: The results showed that the use of a magnetic marker could relatively accurately reflect the fracture pattern inside the rock-like material (RLM). Design/methodology/approach: This study investigated the internal structure and fracture pattern of a fractured RLM. Magnetized iron oxide powder, which was used as a magnetic marker, was mixed with water and glue to form a magnetic slurry, which was subsequently injected into a fractured RLM. After the magnetic slurry completely filled the cracks inside the RLM and became cemented, the distribution and magnitude of the magnetic field inside the RLM were determined using a three-dimensional (3D) magnetic field imaging system. Findings: A model for determining the magnetic field strength was developed using MATLAB. Originality/value: This model of 3D magnetic will further be used as a finite element tool to simulate and image cracks inside the rock. [ABSTRACT FROM AUTHOR]

Centrifugal compressor is exposed to pulsating backpressure due to the movement of intake valves in internal combustion engine. The performance of compressor deviates from the steady performance map, which affects the matching between turbocharger and engine. The behavior of compressor system at pulsation conditions are investigated via an in-house developed 1D unsteady code validated by experimental results. The influence of pulse frequency, magnitude and compressor characteristic curve on the compressor transient responses, including filling-emptying effect and wave dynamics, are analyzed. Results show that the strength of wave dynamics grows stronger with the increasing of pulse frequency, while the strength of filling-emptying effect increases first then decreases. The rise of pulse magnitude results in an almost linearly increasing of filling-emptying effect, while it can hardly affect the wave dynamics. Furthermore, the influence of pulsation magnitude and frequency represents the influence of local pressure gradient, and a correlation as quadratic curve can be evaluated between the pressure gradient and compressor unsteadiness. On the other hand, the influence of operating point, including the average mass flow rate and the slope of characteristic curve, is confirmed to be evidently smaller, comparing to the influence of pulsation frequency and magnitude. This study is helpful to estimate the behavior of compressor and the discrepancy of performance when operating at unsteady environment or matched with engine. [ABSTRACT FROM AUTHOR]

Seawater electrolysis with clean hydrogen energy has bright prospects due to the abundant reserves of seawater on our planet. However, the highly desirable direct seawater splitting with efficient electrocatalyst is still lacking. Herein, Co‐doped metallic VS2 nanosheets with modulated electronic structures and numerous exposed edges were proposed and evaluated as superior catalysts for hydrogen evolution from seawater. The enlarged number of edges through reducing nanosheet size and enriching sulfur defects by Co doping contribute to numerous active sites exposed, leading to desirable catalytic performances. The Co‐doped VS2 nanosheets with 10 % V substituted by Co exhibit excellent catalytic performance in simulated seawater with an onset potential of 196 mV and possesses long‐term stability without obvious current decay after 12‐h test. Moreover, this sample also delivers lower overpotentials of 234 mV at −10 mA cm−2 in acid media. The study can further broaden the development of vanadium chalcogenides in seawater catalysis. [ABSTRACT FROM AUTHOR]

Wear particle image analysis is an effective method to detect wear condition of mechanical devices. However, the recognition accuracy and recognition efficiency for online wear particle automatic recognition are always mutual restricted because the online wear particle images have almost no texture information and lack clarity. Especially for confusing fatigue wear particles and sliding wear particles, the online recognition is a challenging task. Based on this requirement, a super-resolution reconstruct technique and partial hierarchical convolutional neural network, SR-PHnet, is proposed to classify wear particles in one step. The structure of this network is composed by three modules, one is super-resolution layer module, the second is convolutional neural network classifier module, and the third is support vector machine (SVM) classifier module. The classification result of the second module is partial input to the third module for precision classification of fatigue and sliding particles. In addition, a new feature of radial edge factor (REF) is put forward to target fatigue and sliding wear particles. The test result shows that the new feature has the capability to distinguish fatigue and sliding particles well and time saving. The comparison experiments of the convolution neural network (CNN) method, support vector machine method (SVM) with and without REF feature, and integrated model of back-propagation (BP) and CNN are produced. The comparison results show that the online recognition speed and online recognition rate of the proposed SR-PHnet model in this paper are both improved markedly, especially for fatigue and sliding wear particles. [ABSTRACT FROM AUTHOR]

The main purpose of this investigation is to study the dynamic characteristics of shut-in and restart process in reservoirs with high water cut and strong vertical heterogeneity. The physical model, which includes three layers with low, medium, and high-permeability from top to bottom, was made according to the similarity law. Water drive test, the first restart test, and the second restart test were conducted, respectively. Water cut, oil recovery, and saturation distribution of the remaining oil were obtained during the tests. On this basis, mechanisms of shut-in and restart process of the reservoir were analyzed. It is concluded that appropriate developing plan such as layering mining and cyclic waterflooding should be implemented for developing strong heterogeneity reservoirs. The shut-in and restart tests showed that closing the water-flooded layer is beneficial for enlarging the sweep volume. Besides, water cut of 98% does not mean the economic limits of waterflooding. Under the effect of capillary force and gravitational differentiation, oil and water will redistribute in the formation. The redistribution of the oil and water, the fluctuation of the pressure difference, and the rebuild of the flow path, which produce parts of the bypassed oil, are the main mechanisms of the recovery enhancement by shut-in and restart operation. It should be noted that the shut-in and restart process indeed prolongs the waterflooding development. However, simply replying on the oil and water distribution under static conditions cannot greatly enhance the oil recovery. [ABSTRACT FROM AUTHOR]