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In recent years, the pseudopotential multiphase lattice Boltzmann method (LBM) has been widely applied in the numerical simulations of complex multiphase flow. However, numerical stability at high Weber (We) and Reynolds (Re) numbers seriously restricts its application. In the present work, the pseudopotential multiphase LBM is developed by introducing the entropic stabilizers to the cascaded collision operator, and thus, the numerical stability is effectively enhanced. The relaxation rates for different order moments are all determined by fluid viscosities and the maximum entropy condition instead of being user-defined. Furthermore, the surface tension and contact angle can be adjusted in a wide range, which extends the application of the pseudopotential multiphase model. The accuracy and capability of the present model to simulate the complex multiphase flow are validated by reproducing the droplet impact on the flat or textured superhydrophobic surfaces. In addition, a droplet impact on the superhydrophobic surface at We = 1280 and Re = 18000 is simulated, in which the Weber and Reynolds numbers have significantly increased. This strongly demonstrates that the present model can enhance the numerical stability in the simulation of large density ratio multiphase flows at simultaneously high Weber and Reynolds numbers, which means the present model can further extend the pseudopotential multiphase LBM to more realistic scientific and technical applications. [ABSTRACT FROM AUTHOR]

Chronic cholestasis liver injury occurs in progressive hepatobiliary diseases that eventually lead to end-stage liver problems without curable treatment. Great advances in the molecular mechanism suggest the therapeutic pathways for the regulation of bile acid (BA) metabolism and inflammation response. Honokiol (HNK) is a natural ingredient from herb Magnolia officinalis that is used for eliminating toxins, reducing stagnation, resolving stasis and enhancing body immunity. In the present study, we designed two dependent experiments for the evaluation of the hepatoprotective and hepatotoxicity effects of HNK. Chronic cholestasis liver injury model was established by 0.1% 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC) containing diet feed for 4 weeks that featured as a ductular reaction, BAs accumulation, fibrosis and inflammatory response. In the first experiment, two dosages of HNK (2 and 10 mg/kg) were daily intraperitoneal injected from day 15 to day 28 for the treatment of chronic cholestasis liver injury. HNK displayed a dosage-dependent reduction of ductular reaction, regulation of BAs metabolism, remission of fibrosis and inhibition of inflammatory response. In the second experiment, the high dosage of HNK (10 mg/kg) was daily intraperitoneal injected into normal control and model mice for 4 weeks. HNK-mediated hepatoprotective effect is mainly involved in the regulation of BAs metabolism, decrease of inflammatory cell infiltration and inhibition of pro-inflammatory cytokines production. Moreover, HNK showed no hepatotoxicity even though the high dosage of HNK treatment for 28 days in control mice resulted in no obvious change in hepatic histopathological and serological changes. In conclusion, HNK exerts dosage-dependent pharmacological effect against DDC diet-induced chronic cholestasis liver injury. Further investigation of the preclinical pharmacodynamics effect and toxicity research about HNK is helpful for active therapeutic drug development for the treatment of cholestasis liver disease. [ABSTRACT FROM AUTHOR]

Design of low-cost and highly efficient electrodes for oxygen evolution is highly desirable for bulk water electrolysis associated with several conversion and storage of the renewable energies. Mixed Ni–Fe catalysts have showed excellent activities towards oxygen evolution reaction (OER), however, the long-term stability at high current densities has not been well-documented. Here we fabricate three-dimensional (3D) self-supported Ni 1-x -Fe x OOH/carbon fiber cloth (CFC) electrodes for highly efficient oxygen evolution through in situ electrochemical activation of the corresponding 3D Ni 1-x -Fe x S/CFC precursors. The activated Ni–Fe electrodes exhibit remarkably enhanced OER activities compared to the pure Ni and Fe catalysts and the highest OER activity is achieved as x = 0.30. To drive current densities of 100 and 200 mA cm −2 , the 3D Ni 0.70 Fe 0.30 OOH/CFC electrode in 1.0 M KOH only requires overpotentials of 200 and 205 mV, respectively, outperforming the commercial IrO 2 catalyst and all previously reported Ni–Fe catalysts. Furthermore, the Ni 0.70 Fe 0.30 OOH/CFC electrode can continuously operate at >350 mA cm −2 over 100 hours with a negligible current loss in 1.0 M KOH. Such excellent activity and robust long-term stability at high current density demonstrate that the 3D Ni–Fe catalysts can applied in industry for large-scale oxygen production. [ABSTRACT FROM AUTHOR]

A facile and efficient strategy is developed to incorporate yolk-shell CoO@Co nanoparticles (NPs) and ZnO NPs with graphene sheets. The diameter and the space between CoO shell and Co yolk are merely 12.0 nm and 1.0 nm, respectively, while the diameter of ZnO NPs is in the range of 4.0–10.0 nm. Due to the small size of NPs and the special structural feature, the resultant graphene-based composite exhibits excellent electromagnetic wave (EMW) absorption properties. Typically, the minimal reflection loss ( R L ) value reaches to −51.1 dB at 11.3 GHz at the absorber thickness of 2.6 mm, and less than −20 dB at the absorber thickness ranging from 2.0 to 5.0 mm. Moreover, the absorption bandwidths corresponding to the R L values below −10 dB (90% of EMW wave energy consumption) is up to 4.7 GHz (from 9.5 to 14.2 GHz) at a thickness of 2.6 mm. Furthermore, the addition amount of the composite into paraffin matrix is merely 20 wt%, less than that of most EMW absorber reported previously. Therefore, such novel hybrid materials can be used as a kind of candidate for lightweight EMW absorbing material. [ABSTRACT FROM AUTHOR]

Glycyrrhiza uralensis Fisch , also called Gan Cao, is a commonly prescribed herb in traditional Chinese medicine. Gan Cao is associated with immune-modulation and antitumor potential though its mechanism of action is not well-known. To explore the effects of different dietary levels of Gan Cao polysaccharide (GCP) on broilers, a total of 400 Avian broiler chickens were randomly divided into 4 groups with 10 replicates of 10 broilers each. The broilers in the control group were fed a basal diet, while those in the experimental groups were fed the basal diet supplemented with 0.5%, 1.0%, and 1.5% GCP, respectively, for 42 d. The results showed a significant increase in the growth performance in the GCP groups. The antibody titer of NDV and the phagocytosis index was higher in the birds with GCP treatment than in the control group, with the 1% GCP addition displaying the highest titer. The Lactobacillus and Bifidobacteria count in the cecum content of the birds in the 1% GCP group was higher compared to the other groups. In conclusion, dietary supplementation with GCP had a substantial impact on the growth performance, immune response, and microflora population in the cecum of the birds, especially at a level of 1% addition. [ABSTRACT FROM AUTHOR]

Based on the analysis of the properties of carbon dioxide, an open carbon dioxide refrigeration system is proposed, which is responsible for the situation without external electricity unit. A model of open refrigeration system is developed, and the relationship between the storage environment of carbon dioxide and refrigeration capacity is conducted. Meanwhile, a test platform is developed to simulation the performance of the open carbon dioxide refrigeration system. By comparing the theoretical calculations and the experimental results, several conclusions are obtained as follows: refrigeration capacity loss by heat transfer in supercritical state is much more than that in two-phase region and the refrigeration capacity loss by remaining carbon dioxide has little relation to the state of carbon dioxide. The results will be helpful to the use of open carbon dioxide refrigeration. [ABSTRACT FROM AUTHOR]

MoO 3 nanorods/Fe 2 (MoO 4 ) 3 nanoparticles composite has been prepared by a hydrothermal method combined with an in situ diffusion growth process. Single cells based on 300 μm LSGM electrolyte have been fabricated with the MoO 3 nanorods/Fe 2 (MoO 4 ) 3 nanoparticles composite anode and a composite cathode consisting of Sr 0.9 Ce 0.1 CoO 3− δ and Sm-doped ceria (SDC). The peak power densities reach 225, 50, 75 mW cm −2 at 900 °C in H 2 , CH 4 and C 3 H 8 , respectively. The cell shows excellent long-term stability at 850 °C. The preliminary results demonstrate that the MoO 3 nanorods/Fe 2 (MoO 4 ) 3 nanoparticles composite is a promising alternative anode for solid oxide fuel cells. [ABSTRACT FROM AUTHOR]

One-dimensional (1D) CuO nanostructures with nanoribbons, scroll-like structure, arrays of CuO nanoparticles and nanorod-like morphologies respectively, have been successfully prepared using the single-crystalline Cu2(OH)2CO3 nanoribbons as precursors for sacrifice-template via heat-treatments. The series of morphologies images for decomposition kinetics process of Cu2(OH)2CO3 nanoribbons as heat-treatment temperature increased are presented in this work. The result demonstrates that the morphologies of the 1D CuO nanostructures obtained are mainly due to the ribbon-like shape of the precursors. The morphologies of CuO nanostructures also strongly depend on the heat-treatment conditions. At relatively low heat-treatment temperature and heating rate, the morphological features of the precursor can be preserved well, while arrays of CuO nanoparticles can be obtained at higher heating rate and CuO rod-like shape can be prepared with increasing heat-treatment temperature. [Copyright &y& Elsevier]

CdS/PSA (Poly(styrene–co-acrylic acid) (St/AA)) core-shell composites “egg” whose major and minor axis is about 400, 200 nm, respectively, have been prepared using PSA ellipsoids as template. Viscoelastic deformation of polyvinyl alcohol was used to convert monodispersed PSA microspheres into uniform ellipsoids with a tightly controlled major-to-minor axis ratio. [Copyright &y& Elsevier]

Cu2Cl(OH)3 nanoribbons with an average diameter of 50 nm in width and several micrometers in length have been synthesized for the first time by exploiting a template-free approach at ambient temperature. The growth mechanism and the optimization conditions to grow the Cu2Cl(OH)3 nanoribbon are investigated. The CuO nanoribbons with well-preserved structures are formed through a heat treatment of Cu2Cl(OH)3 nanoribbons. The advantages of our method for the single-crystalline Cu2Cl(OH)3 nanoribbons lie in the mild reaction conditions and simple operation, which permit large-scale production at a low cost. In addition, it provides a practical method to prepare one-dimensional CuO materials. [Copyright &y& Elsevier]

The Mg(OH)2 nanorods with diameters of ca. 8–10 nm and lengths of more than 250 nm have been prepared by a novel liquid–solid arc discharge technique. X-ray diffraction (XRD) showed that the Mg(OH)2 nanorods were well-crystallized with the hexagonal structure. The structure features were also analyzed by TEM, HRTEM, and FTIR. Based on the investigation of the influence of current density, discharge time and pH of the electrolyte, the possible growth mechanism of the Mg(OH)2 was discussed. [Copyright &y& Elsevier]

In order to effectively avoid the side effects induced by multiple components and tedious synthesis process, a simple therapy system based on one material to simultaneously realize both photothermal therapy (PTT) and photodynamic therapy (PDT) under single laser irradiation will promote the overall phototherapeutic efficiency and make the PTT/PDT system easier to operate. Here, by using transferrin (Tf) as protein template, ultrasmall CuS@transferrin nanodots (CuS@Tf NDs) were successfully synthesized through a facile one-pot protein-based biomineralization method. The obtained CuS@Tf NDs exhibited not only excellent photothermal conversion ability (34.4%) but also high photoactivated formation of reactive oxygen species (ROS) upon 980 nm near-infrared (NIR) irradiation. By loading the drug doxorubicin (DOX) to CuS@Tf NDs, a synergistic therapy system with multiple therapeutic effects combined PTT, PDT, chemotherapy (CT) and tumor targeting properties could be perfectly implemented together by CuS@Tf-DOX NDs without any complicated post-modification process. Results from the in vitro cell experiments confirmed that these CuS@Tf-DOX NDs could produce excellent effect on cancer cells with 88.5% cell inhibition rate. In comparison with the complicated systems based on "multiple-components-in-one" strategy, this therapy system based on one single material but possess multifunctional purpose is easy to operate and more suitable for clinical applications. A synergistic therapy system with tumor targeted photothermal therapy/photodynamic therapy/chemotherapy multiple therapeutic effects could be perfectly implemented by CuS@transferrin-doxorubicin (CuS@Tf-DOX) nanodots under single Near-infrared laser irradiation. Unlabelled Image • CuS@transferrin nanodots (NDs) were obtained through protein biomineralization method. • The prepared NDs with excellent biocompatibility and intrinsic promising specificity • The NDs could simultaneously realize photothermal and photodynamic therapy. • Multifunctional theranostic nanoplatform with a just clear and simple structure [ABSTRACT FROM AUTHOR]

Failures of fiber-resin composite structures are closely related to the fiber weaving methods (FWM). The diversity of damage mechanisms of glass fiber-resin plastic (GFRP) composite materials resulting from various FWM is analyzed by an acoustic emission (AE) technique in this paper. Firstly, uniaxial tensile tests of three types of samples are carried out until failure with simultaneous recording of AE signals. Then, with the wavelet transform (WT) and fuzzy C-means (FCM) identification clustering, the analyzing outcomes display that AE parameters of diverse FWM specimens are variant. Furthermore, results illustrate that the fractures of axial fibers are delayed due to the interweaving effect of oblique fibers and the oblique fiber interweaving causes the shear force which changes the value of amplitude, ringing count, energy and duration. Lastly, finite element method (FEM) is implemented to confirm the capability of an AE-based approach to identify the damage of various fibrous layers. The conclusions from this study are also useful for developing high quality fiber-resin composite materials and further improving the accuracy of on-line monitoring of fiber-resin composite structural health. [ABSTRACT FROM AUTHOR]

• A new and high-precision test bench for the shear adhesion strength of ice-substrate interface is obtained. • The subject of this paper is impact ice and the experiments are performed in an icing wind tunnel, which makes the results close to the practical situation. • Glaze ice demonstrates a rise in its shear adhesion strength at lower temperatures, while the change trend is the opposite for rime ice. • The growing liquid water content (LWC), rough surfaces, and surface painting will enhance the interface adhesion. • Superhydrophobic surfaces have proven to possess a significant reduction in adhesion strength at higher temperature. Aircraft icing has a detrimental effect on flight safety. The design of aircraft anti-icing/de-icing systems requires a thorough comprehension of the adhesion between the ice and the substrate. In this research, the multi-hole rotating cylinder method (MHRC) is developed in an icing wind tunnel. Simulations of interfacial stress show that ice thickness does not change the evenness of stress, whereas reducing the contact area can impair uniformity. Moreover, the ice layer would not experience any cohesive damage during the experiments. The shear ice adhesion strength is evaluated using the methodology outlined in this research. At lower temperatures, glaze ice demonstrates a rise in its shear adhesion strength, while the change trend is the opposite for rime ice. The lowest adhesion strength is observed at the medium volume diameter (MVD) of 45 µm. Furthermore, the growing liquid water content (LWC), rough surfaces, and surface painting will enhance the interface adhesion of ice to the substrate to varying degrees. Stainless steel substrate exhibits higher adhesion strength with ice as compared to aluminum and titanium. In addition, superhydrophobic surfaces have proven to possess a significant reduction in adhesion strength at higher temperature. The proposed experimental method and platform afford accurate measurements of the shear adhesion strength of impact ice in the icing wind tunnel. [ABSTRACT FROM AUTHOR]

Here we presented an ultra water-repellent surface with the ternary composite structures, expecting to provide an inspiration to the application research. Our strategy is to design macro ridge structures on the superhydrophobic surface, which is prepared by modifying the composite micro-nanoscale hierarchical structures with FAS-17. The effect of micro-nanoscale hierarchical structures on the non-wettability were firstly analyzed and examined for achieving a perfect unity of microstructures and property. On this basis, we designed the macro ridge structures and obtained the final sample surface, which could not only display a strong superhydrophobicity with the apparent contact angle reaching 161° and the contact angle hysteresis reducing to 1.5°, but also exhibit the capacity to compel the impact water droplet to bounce off within an extreme short time (5.5 ms). [ABSTRACT FROM AUTHOR]

The increasingly serious electromagnetic radiation urgently call for high performance electromagnetic wave (EMW) absorbers. Hollow carbon nanostructures are promising for lightweight EMW absorbers. However, due to lack of sufficient polarization centers, the EMW absorption property of hollow carbon nanosturctures is still unsatisfactory. Herein, we develop a double-salt template method for fabrication of N, S-codoped graphitic carbon nanoframes (GF) that anchored on the graphene sheets (GS). The GFs in the sample (N, S-GF/GS) have a width of about 51 nm and a wall thickness of only 4.8 nm. Furthermore, the graphene plane in the GF is perpendicular to the graphene plane in the GS, leading to the formation of numerous interfaces between the graphene planes perpendicular to each other. Theoretical calculations indicate that the interfaces can induce the interfacial polarization loss, and the N, S co-doping can cause dipole polarization loss, both of which enhance the EMW absorption performance of the N, S-GF/GS. The minimal reflection loss and efficient absorption width of the N, S-GF/GS at a low filler ratio of 10 wt% are -45.64 dB at the matching thickness of 2.3 mm and 4.35 GHz with the thickness of 1.5 mm, respectively, superior to most of carbon-based absorbers. Our proposed method opens a promising way for high-performance EMW absorbers. [Display omitted] • A double-salt template method was proposed for fabricating N, S-codoped carbon nanoframes (GF) on graphene (GS). • The GFs have a width of about 51 nm and a wall thickness of only 4.8 nm. • The graphene planes in GF and GS are perpendicular to each other, leading to numerous interfaces. • The effective absorption bandwidth of the designed absorbers reached 4.35 GHz. • The mechanism about the synergisty of interface and N, S co-doping was uncovered. [ABSTRACT FROM AUTHOR]

Three−dimensional (3D) hierarchical nano−microstructures have shown unprecedented physicochemical properties. However, it still remains great challenge to construct well−defined architectures with 3D hierarchical feature. Herein, we develop an electrospinning technique followed by a high−temperature carbonization process to fabricate N−doped carbon fibers (NCF) with N−doped carbon nanotubes (NCNTs) vertically grown on the surface of NCF using the Fe species as catalysts. In the 3D hierarchical structures, the Fe 3 C nanoparticles (NPs) are embedded within NCF matrix, while the Fe NPs are encapsulated within NCNT. Due to the unique structural feature, the as−prepared hierarchical structure exhibits excellent electromagnetic wave absorption performance with an absorption bandwidth of 4.0 GHz and a minimum reflection loss of −49.56 dB with a thickness as low as 1.50 mm. Experimental and theoretical studies indicate that the enhanced electromagnetic wave absorption performance of the hierarchical structure can be explained by the increased conduction loss induced by the introduction of metallic NPs and formation of 3D conductive networks, and the enhanced polarization loss caused by the additional interfaces and defects in the hierarchical structure. This work provides an efficient way to fabricate 3D architecture for high−efficiency electromagnetic wave absorption. [Display omitted] • The 3D hierarchical structure (Fe 3 C@NCF/Fe@NCNT) is synthesized. • In the structure, Fe 3 C NPs are embedded within NCF, while the Fe NPs are in NCNT. • Fe 3 C@NCF/Fe@NCNT exhibits good microwave absorption property with a low thickness. • The metals, interfaces and 3D networks are responsible for the absorption property. [ABSTRACT FROM AUTHOR]

It is highly desirable for electromagnetic wave (EMW) absorbers to have a low high filler ratio in matrix and low matching thickness. Herein, atomically dispersed Mn sites are introduced into N-doped carbon nanotubes (Mn−N x /NCNT) to this aim. Structural characterizations indicate that the as-fabricated Mn−N x /NCNT exhibits tubular morphology with a large surface area of 295.56 m2 g−1 and the Mn sites are atomically dispersed in the NCNT with a loading of 1.56 wt%. Benefiting from the unique structural advantages, Mn−N x /NCNT has excellent EMW absorption property, showing an effective absorption bandwidth of 4.15 GHz at a filler ratio of only 7% and a matching thickness of only 1.7 mm. The experimental measurements of electromagnetic parameters and density functional theory calculation results indicate that electronic structure and polarizability of the NCNTs are adjusted by the atomically dispersed Mn sites, leading to the increase in conduction and polarization losses of Mn−N x /NCNT, and thus in the EMW property. Our results demonstrate that hollow nanotubes containing metal single-atoms are potential EMW absorbers with a lightweight feature. [Display omitted] [ABSTRACT FROM AUTHOR]

The actuator disc (AD) model combined with the Reynolds-averaged Navier-Stokes (RANS) model has been demonstrated as the most effective approach for simulating wind farm wakes due to its computational efficiency and acceptable accuracy. However, challenges remain in defining the reference inflow wind speed for the AD model and identifying a robust turbulence model for the RANS method. To solve these issues, two strategies for establishing the AD model (AD- up1D model and AD- local model), along with four turbulence models (standard k - ε , SST k - ω , linear pressure-strain RSM and modified RSM), are comprehensively validated here to predict multiple wakes within two representative wind farms. The temporal variability of multiple turbines' power output and the significant impact of wind direction on the power is particularly emphasized. Overall, this study indicates that the proposed AD- local /Mod RSM method facilitates a realistic wake recovery in the cumulated wake flow and agrees well with the field measurements. It consistently performs well, never ranking last in any test cases, with percentage deviations ranging from 1.8% to 9.0%. Most importantly, this study evaluates the strengths and weaknesses of each AD/RANS method and provides recommendations for wind farm design purposes. • Two typical wind farms featuring regular and irregular layouts are investigated. • A systematic evaluation of the AD/RANS method setting approaches are conducted. • The proposed AD- local /Mod RSM method facilitates a realistic cumulated wake effect. • Identify an effective AD/RANS model for predicting multiple wake interactions. • The quality of each turbulence model is highly related to the wind sector angle. [ABSTRACT FROM AUTHOR]

• Sufficient internal cavities of nanosphere improves impedance matching properties. • The multi-component heterostructure of Fe 3 O 4 /FeS x enhances interfacial polarization. • Fe 3 O 4 /FeS x nanospheres have optimal structural integrity and crystallinity at 400°C. • Hollow Fe 3 O 4 /FeS x nanospheres and graphene aerogel improve lightweight properties. • The RL and EAB of the synthesized materials are -43.03 dB and 4.24 GHz, respectively. The fabrication of materials featuring hollow structures or multi-component heterostructures effectively enhance the performance of electric/magnetic loss and improve the impedance matching properties of absorbers. In this work, by precisely controlling the sulfidation temperature at 400°C and incorporating rGO, we successfully obtained Fe 3 O 4 /FeS x -rGO aerogel materials with exceptional structural integrity and crystallinity. The electromagnetic parameter analysis and calculation confirm the enhancement of impedance matching, interface polarization, electrical conductivity, and dielectric loss capability of the hollow structure and multi-interface heterostructure; while computer simulation technology results verify the effective attenuation capability of the absorber for electromagnetic energy under practical application conditions. As a result, the reflection loss of Fe 3 O 4 /FeS x -rGO reach −43.03 dB at a thickness of only 2.0 mm and the effective absorption bandwidths is 4.24 GHz at a thickness of 1.6 mm. This multifactorial synergistic enhancement mechanism provides a new idea for the design and preparation of high-performance electromagnetic wave absorbing materials. [Display omitted] [ABSTRACT FROM AUTHOR]

In wind farm design, accurately predicting the wake turbulence level is crucial for turbine power and load evaluation. However, a knowledge gap still exists on the characteristics of wake turbulence, meanwhile there has been little work on the development of related engineering models. In view of this, firstly, one-dimensional analytical models that can estimate the wake width and maximum wake turbulence level at any streamwise positions are proposed and validated. Based on these, a highly simple three-dimensional cosine shape (3D-COTI) model is proposed for estimating the wake turbulence intensity in an effective way. Moreover, by taking into account the wind shear and ground effects, this proposed model is capable of describing the anisotropic property of the 3-D wake field. Afterwards, model evaluations are performed through several test cases consisting various types of turbines operating under a wide range of inflow conditions. Overall, the proposed model shows a good agreement with the measurements about the spatial distribution of turbulence enhancement within the wake flow. Because of its good accuracy, simplicity and universality, the present model has potential for large-scale wind farm applications. [ABSTRACT FROM AUTHOR]

Metal-organic frames derived magnetic nanostructures have potential applications in various fields. However, the magnetic particles in the derivatives are frequently agglomerated, limiting their physicochemical properties. Herein, we cross CoZn-MOF particles through ultra-long MnO 2 nanowires (MnO 2 @CoZn-MOF) as precursor for high-performance functional materials. After the carbonization of the MnO 2 @CoZn-MOF, MnO 2 nanowires were transformed into MnO nanowires coated with N -doped carbon layer (MnO@CN), while the CoZn-MOFs were converted into N -doped carbon polyhedron particles encapsulated with Mn 3 Co 7 alloy nanoparticles (Mn 3 Co 7 @CN), leading to the formation of hierarchically pearl necklace-like nanostructure (CoMn@CN). The magnetic Mn 3 Co 7 @CN nanoparticles are separated uniformly along one-dimensional MnO@CN nanowires, and thus the self-agglomeration of magnetic nanoparticles is avoided efficiently. As a result, the CoMn@CN exhibits excellent electromagnetic wave absorption property with an effective absorption bandwidth of 5.24 GHz as the matching thickness is only 2.0 mm. Experimental results and theory calculations indicate that the improved conductive loss and dielectric relaxation loss caused by abundant heterointerfaces and the electronic interaction between Co and Mn atoms are responsible for the excellent electromagnetic wave absorption performance. Our strategy provides an efficient way for the synthesis of high-performance MOFs-derived nanostructures. [Display omitted] [ABSTRACT FROM AUTHOR]

Most existing analytical wake models have been designed to represent the velocity distribution of the far wake region behind a wind turbine, but fail to reproduce the trend of the near wake. In order to meet the demand for both near and far wake velocity predictions, a concise three-dimensional dual-cosine shape (3D-COU) model is proposed. Moreover, by taking into account the wind shear and ground effects in the vertical direction, this model is capable of describing the anisotropic property of the 3-D wake field and is much closer to the reality. The proposed model is then calibrated and validated through a series of test cases, including different scales of turbines that are operating under a wide range of inflow conditions, and meanwhile the reference data resource is diverse. Overall, the results demonstrate that the 3D-COU model can accurately predict the variations of the wake velocity in both the vertical and horizontal directions throughout the whole wake region. Given its good accuracy, simplicity and applicability, this model provides the potential to effectively address practical problems in wind energy projects. [ABSTRACT FROM AUTHOR]

Rational design of the morphology and structure is important for the functional materials to improve their physicochemical properties. Herein, we design hierarchically three-dimensional (3D) structures assembled with yolk-shelled spheres-supported nitrogen-doped CNTs (NCNTs) using Ni(OH) 2 @SiO 2 core-shelled spheres as precursors for electromagnetic wave absorption. In the 3D structures, the yolk materials are SiO 2 spheres, while the shell materials are N-doped carbon layers containing Ni, Si and O elements. Importantly, The NCNT arrays with encapsulated Ni NPs are branched out from the yolk-shelled spheres. The hierarchical structures feature the merits of both yolk-shelled and 3D structures. Furthermore, the SiO 2 sphere in the 3D structure can tune the electrical conductivity, affording our hierarchically 3D structure better impedance matching characteristic for electromagnetic wave absorption. As a result, the reflection loss and effective absorption bandwidth of our optimal 3D structure can reach −59.90 dB and 4.24 GHz, respectively, while the thickness of the absorbing film is only 1.4 mm, superior to most of reported carbon-based absorbers. The present method for the regulation of the structure and morphology provides an efficient way to construction of high-performance electromagnetic wave absorbers. [Display omitted] • Yolk-shelled sphere-supported nitrogen-doped carbon nanotubes were fabricated. • The hierarchical structures have the merits of both yolk-shelled and 3D structures. • SiO 2 sphere in the 3D structure can optimize impedance matching characteristic. • The absorption bandwidth of the sample is 4.24 GHz with a thickness of 1.4 mm. [ABSTRACT FROM AUTHOR]

Considering serious exhausted non-renewable energy resources and electromagnetic radiation pollution issues, it is quite urgent to exploit multifunctional material for realizing both the conversion sustainable energy sources and protection of electromagnetic radiation pollution. Herein, we develop a facile and high-yield preparation route to fabricate a multifunctional material consisted of CoFe alloy nanoparticles encapsulated in nitrogen doped carbon nanotubes arrays grown on both sides of reduced graphene oxide (CoFe@N-CNT/rGO). CoFe@N-CNT/rGO displays excellent properties in the field of rechargeable Zn-air battery and electromagnetic wave absorption. CoFe@N-CNT/rGO shows bifunctional electrocatalytic performances toward oxygen reduction reaction and oxygen evolution reaction, favorably comparable to that of commercial catalysts (Pt/C and IrO 2). Furthermore, the assembled liquid and all-solid-state rechargeable Zn-air batteries with CoFe@N-CNT/rGO as air cathode display good charging–discharging performance. As electromagnetic wave absorbing material, CoFe@N-CNT/rGO shows the minimal reflection loss of −33.2 dB at 13.3 GHz, superior to reported carbon-based electromagnetic wave absorbing materials. Based on excellent electromagnetic absorption performance, electromagnetic energy conversion device is designed to realize reasonable utilization and conversion of the absorbed electromagnetic energy. These encouraging results lay a solid foundation for development the multifunctional material and provide an effective strategy for simultaneously solving energy crisis and electromagnetic radiation problems. [Display omitted] • 3D rGO-supported N-doped CNT arrays (N-CNT/rGO) were fabricated by a facile method. • The N-CNT/rGO has multifunctionality for catalyzing ORR and OER and absorbing EMW. • The ORR activity of N-CNT/rGO is comparable to that of the commercial Pt/C. • EMW absorption property of N-CNT/rGO is outperforms most of carbon-based absorber. • The model device for reusage of waste electromagnetic energy is designed. [ABSTRACT FROM AUTHOR]

Carbon nanotubes (CNTs) have important application in electromagnetic wave absorption due to their unique tubular structure, lightweight feature and high electrical conductivity. However, sole CNTs suffer from bad impedance matching characteristic, leading to unsatisfactory absorption performance. Herein we propose a universal SiO 2 -assisted strategy to fabricate Ni nanoparticle-encapsulated nitrogen-doped CNTs on the SiO 2 spheres (Ni@NCNT@SiO 2). Due to the spatial separating effect, the formation of large metal aggregates and large-sized NCNTs in the products are avoided effectively. In the meanwhile, the ideal impedance matching characteristic is also achieved due to the introduction of the non-conductive SiO 2 spheres. As a result, even with a low matching thickness (1.3–2.0 mm), the reflection loss values of Ni@NCNT@SiO 2 reaches −30 dB. Furthermore, the proposed method can be also used to fabricate Fe 3 C/Fe@NCNT@SiO 2 and Co@NCNT@SiO 2 with satisfactory absorption properties, demonstrating its universality for synthesis of high-performance absorbers based on CNTs. Image 1 • A universal SiO 2 -assisted method is proposed to fabricate magnetic NP-embedded NCNTs. • The size and impedance matching characteristic of the NCNTs are tailored effectively. • The absorption bandwidth of the NCNTs is 4.14 GHz with a thickness of merely 1.5 mm. • The proposed method can be extended to design other high-performance absorbers. [ABSTRACT FROM AUTHOR]