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The blood‐brain barrier (BBB) poses a significant challenge in delivering therapeutic agents for brain diseases due to its high selectivity against foreign substances. This limitation greatly hampers the effectiveness of conventional chemotherapeutic drugs in treating brain cancers. In response, lipid‐based nanoparticles (LNPs) have emerged as a promising approach, offering opportunities for targeted drug delivery by conjugating targeting ligands onto their surface. This review provides a comprehensive overview of recent advancements in utilizing LNPs to traverse the BBB for enhanced transport of bioactive compounds into the brain, specifically for cancer treatments. Beginning with an exploration of the biological structure and functions of the BBB and the blood‐brain tumor barrier (BBTB), the review highlights the advantages presented by LNPs. Subsequently, it delves into strategies for surface modification of nanoparticles to enhance BBB targeting and improve efficacy in brain cancer treatment. Finally, the review offers insights into future prospects for designing the next generation of LNPs. The review presented herein aims to contribute to the ongoing efforts in overcoming the challenges associated with BBB penetration, ultimately advancing therapeutic strategies for brain cancer and other neurological disorders. [ABSTRACT FROM AUTHOR]

Government websites are currently important for providing information and services to citizens. It is a crucial task to evaluate the performance of each government website. The traditional evaluation processes based on experts are criticised as being subjective and cannot work in real time. This article proposes a framework and automatic assessment system for evaluating the performance of government websites in real time. To test the proposed framework and the automatic assessment system, we evaluate and classify 70 websites from Shaanxi Province of China. This article provides guidance for government agencies, managers of government websites and researchers. [ABSTRACT FROM AUTHOR]

The application of erythropoietin (EPO) can bring about a rare but serious complication called anti‐EPO antibody‐mediated pure red cell aplasia (PRCA). Once the disease is diagnosed, EPO administration should be stopped immediately. However, after the removal of the anti‐EPO antibody, treating anaemia in these patients with chronic renal disease with EPO therapy is difficult, as restarting EPO therapy risks the recurrence of anti‐EPO antibody‐mediated PRCA. A 26‐year‐old man with anaemia related to renal failure, who was administered recombinant human EPO subcutaneously, developed anti‐EPO antibody‐mediated PRCA. After removal of antibodies by treatment with corticosteroids and cyclosporine, therapy for anaemia of chronic renal disease with roxadustat achieved good results. Roxadustat is a new type of drug for the treatment of anaemia, and it can stimulate endogenous EPO within or near the physiologic range and increase haemoglobin levels. [ABSTRACT FROM AUTHOR]

Complex automatic protection functions are being added to the onboard software of the Alpha Magnetic Spectrometer. A hardware-in-the-loop simulation method has been introduced to overcome the difficulties of ground testing that are brought by hardware and environmental limitations. We invented a time-saving approach by reusing the flight data as the data source of the simulation system instead of mathematical models. This is easy to implement and it works efficiently. This paper presents the system framework, implementation details and some application examples. [ABSTRACT FROM AUTHOR]

Lithium–Zinc ferrite hollow microspheres (LiZn FHMs) doped with La and Mg were synthesized by Fe + Zn + Fe 2 O 3 + O 2 + Li 2 CO 3 reactive system based on self-reactive quenching technology. Influence of La and Mg doping on the surface morphology, phase structure and microwave absorption properties of LiZn FHMs were investigated. The results show that the surface morphology of LiZn FHMs changes little and are still composed of unnoticeable multi-shape crystal grains, whether they are doped or not. The phases are mainly made up of Fe 3 O 4 , Fe 2 O 3 , Li 0.435 Zn 0.195 Fe 2.37 O 4 and Li 0.5 Fe 2.5 O 4 without doping. The phases remain unchangeable after Mg doping, while LaFeO 3 appears in the phase components after La doping. When LiZn ferrites are without doping, their minimum reflectivity at 4 mm is −14 dB at 7.5 GHz, and the effective absorption frequency band less than −10 dB is 6.4–8.6 GHz, with the bandwidth of 2.2 GHz. Compared with that without doping, the minimum reflectivity increases after Mg doping, and the effective absorption frequency band less than −10 dB disappears. After La doping, the minimum reflectivity is −30.2 dB at 6.2 GHz, and the effective absorption frequency band is 4.7–7.7 GHz, with the bandwidth of 3 GHz. It is found from the present investigations that the microwave absorption properties are improved after La doping, and those of LiZn FHMs after Mg doping are reduced. [ABSTRACT FROM AUTHOR]

Al + Fe 2 O 3 + BaO 2 and NaNO 3 as the reactive system and the foaming agent, respectively, are used to prepare barium ferrite hollow microspheres (BFHMs) by self-reactive quenching technology based on flame spraying technology, self-propagating high-temperature synthesis (SHS) technology and quick chilling technology. Effects of NaNO 3 on the particle size, morphology, phase structure and microwave absorption properties of BFHMs are investigated through SEM, XRD, particle size analyzer, high-speed camera and vector network analyzer. The results show that, after adding 10 wt.% NaNO 3 , the average particle size of BFHMs decreases initially from 28 μm to 6 μm, as well as the particle distribution gets narrower. Micro-nano lamellar crystals appear on the surface of BFHMs, with the dimension ranging from 500 nm to 2 μm. BaFe 2 O 4 and Fe 3 O 4 , which have spinel structures, can be seen in XRD, and they are beneficial for microwave absorption properties. The real part ( ɛ ′), imaginary part ( ɛ ″) of permittivity, and the imaginary part of permeability ( μ ″) increases in 0.5–18 GHz. The real part ( μ ′) of permeability increases in 0.5–10.3 GHz, while decreases in 10.3–18 GHz. The microwave absorption properties are improved greatly, and the minimum reflectivity decreases from −3.1 dB to −9.8 dB. The reasons for improvement of microwave absorption properties after adding NaNO 3 foaming agent may be the decreasing of the particle size of BFHMs, the appearance of ferrites (BaFe 2 O 4 and Fe 3 O 4 ) with spinel structure and special micro-nano tabular crystals. Magnetoplumbite-type barium ferrites (BaFe 12 O 19 ) hollow microspheres are obtained after heat-treatment and the microwave absorption properties are further improved. [ABSTRACT FROM AUTHOR]

• Crystalline and amorphous LiZn ferrites hollow microspheres (LiZn FHMs) were prepared. • Self-quenching technology was first used to prepare amorphous LiZn FHMs. • Compared with Crystalline LiZn FHMs, the microwave absorption properties of amorphous ones in low frequency are improved. • Appearance of "rheology unit" is the main reason for improvement of microwave absorption properties in low frequency. The lack of research on low-frequency absorbing materials working at frequencies lower than 8 GHz makes it difficult to meet the military needs of the large wavelength electromagnetic shielding. In this study, crystalline and amorphous lithium zinc ferrites hollow microspheres (LiZn FHMs) were prepared by self-reactive quenching technology, based on Fe+Zn+Fe 2 O 3 +O 2 +Li 2 CO 3 reactive system, using distilled water and 15 wt% NaCl solution as cooling medium, respectively. Effect of cooling medium on the formation mechanism and microwave absorption properties in low frequency range for two kinds of LiZn FHMs was studied. The results show that LiZn FHMs surface with distilled water as cooling medium has polygonal crystal structure. While the surface of LiZn FHMs is smooth by using 15 wt% NaCl solution, and XRD patterns prove that LiZn FHMs are of amorphous structures. When the cooling medium is changed from distilled water to NaCl solution, the magnetic loss of amorphous LiZn FHMs changes from double loss mechanism (natural resonance and eddy current loss) to a single loss mechanism (natural resonance). Compared with crystalline materials, the emergence of "rheology unit" and the change of magnetic loss mechanism are the main reasons for the improvement of microwave absorption properties in low frequencies. When the thickness of the amorphous sample is equal to 2 mm, the minimum reflectivity is −29.8 dB, and the corresponding frequency is 7.1 GHz. The absorption frequency band below −10 dB is 5.3–10.3 GHz, and its bandwidth is 5 GHz. This effectively meets the low frequency new absorbent "thin, light, wide and strong" demand, and it could be promising in the application of invisible coatings on the weapon equipments. The survival performances of weapon equipments in the complex electromagnetic field are expected to be improved. [ABSTRACT FROM AUTHOR]

The proposed method presents a scheme to modify the surface of the glass substrate using the piranha solution and to fabricate the conducting layer of the Through-glass Via (TGV) by the glucose-Ag electroless plating to achieve TGV metallization. The arithmetic mean deviation of the surface contours (Ra) for the substrates increases from 0.001 to 0.135. The contact angle of the substrates (unmodified and modified) is reduced to 6.4° and 12.2°, respectively. The sensitization process with SnCl 2 and the activation process with silver ammonia solution are conducted using the glucose as the reducing agent to prepare the silver seed layer covered in the TGV through-vias with a high aspect ratio (9:1). The adhesion between the metal coating and the surface is measured by the 3M tape and chemical mechanical polishing (CMP). The metal coating adheres well to the surface-modified substrate without peeling off, which can satisfy the demands for the electroplating and CMP processes. [ABSTRACT FROM AUTHOR]

Antimicrobial resistance (AMR) poses a global health crisis demanding innovative solutions. Traditional antibiotics, though pivotal over the past century in combating bacterial infections, face diminished efficacy against evolving bacterial defense mechanisms, especially in Gram‐negative strains. This study explores self‐assembled ionizable lipid nanoparticles (LNPs) with the incorporation of two ionizable lipid components (one cationic, one anionic) in nanocarriers for advanced antimicrobial drug delivery of the broad‐spectrum antibiotic Piperacillin (Pip). Incorporating cationic ionizable lipid ALC‐0315, recognized as a functional lipid in the Pfizer‐BioNTech mRNA‐based SARS‐CoV‐2 vaccine, into LNPs allowed mesophase transition, pH responsiveness, and ionization behavior in acidic environments found in sites of bacterial infections, to be studied using synchrotron small angle X‐ray scattering, dynamic light scattering, and a 2‐(p‐toluidino)‐6‐naphthalene sulfonic acid assay. Incorporating another anionic ionizable lipid, oleic acid not only modulates the LNPs' physicochemical properties, such as size, internal phase nanostructure, and surface charge but also synergistically enhances the antimicrobial potency together with ALC‐0315 with a benefit enhancing permeability and fusion with bacterial membranes. This study introduces a strategy for tailoring ionizable lipid compositions in LNPs, providing a new approach to antimicrobial treatment contributing to the fight against AMR. [ABSTRACT FROM AUTHOR]

• Pine sawdust was fractionated in an ethanol-water mixed solvent (1:1, v/v). • Effects of various catalysts on lignin products were studied at 180 °C for 60 min. • 59 % crude lignin was obtained with 15 % H2SO4 catalysis. • Crude lignin obtained with 15 % formic acid catalysis had a purity of 55 %. • Crude lignin obtained under 15 % NaOH catalysis had a purity of 22 %. A cost-effective process has been developed for fractionating pine sawdust into lignin and cellulose fractions in an ethanol-water mixed solvent. The effects of temperature, different types of catalysts (i.e., strong acid, weak acid and alkali), and residence time, with respect to yields and purity of the crude lignin (degraded products) and crude cellulose (solid residue) were investigated. It is found that the purity of crude lignin was higher but with a lower product yield under a weak acid or alkali catalysis in comparison to strong acid treatments. According to the analysis results, the optimal conditions for fractionation process were as follows: a mixed solvent of ethanol-water (1:1, v/v), 15 % formic acid (based on dry biomass), 180 °C, and 60 min. The yield of the resulted crude lignin was 29.2 % with a purity of 54.6 %, and yield of crude cellulose was 64.6 % with a high purity of 84.3 %. [ABSTRACT FROM AUTHOR]

Background: Anemia is one of the main complications of chronic kidney disease especially kidney failure, which includes treatment with erythropoiesis-stimulating agents and iron supplementation, including intravenous and oral iron. However, intravenous iron may pose limitations, such as potential infusion reactions. Oral iron is mainly composed of divalent iron, which can excessively stimulate the gastrointestinal tract. Iron polysaccharide complex capsules are a novel oral iron trivalent supplement with higher iron content and lower gastrointestinal irritation. However, since high-quality evidence-based medicinal support is lacking, it is necessary to conduct clinical studies to further evaluate the effectiveness and safety of oral iron polysaccharide complex in chronic kidney disease patients.Methods: This randomized controlled trial uses an open-label, parallel group design, where the efficacy and safety of maintenance hemodialysis (MHD) participants is evaluated. The experimental group is assigned erythropoietins and iron polysaccharide complex (two capsules each time, bid), and the control group is assigned erythropoietin and sucrose iron (100mg, 2w) injection. Participants (aged 18-75 years) undergoing maintenance hemodialysis were considered for screening. Inclusion criteria included hemoglobin (Hb) ≥110g/L and < 130g/L, transferrin saturation (TSAT) > 20% and < 50%, and serum ferritin (SF) > 200μg/L and < 500μg/L. Exclusion criteria included acute or chronic bleeding, serum albumin < 35g/L, hypersensitive C-reactive protein (HsCRP) > 10 mg/L, and severe secondary hyperparathyroidism (iPTH ≥ 800 pg/mL). Full inclusion and exclusion criteria are described in the "Methods" section. The primary endpoint is TSAT of the participants at week 12. Secondary endpoints include Hb, SF, hematocrit (Hct), HsCRP, pharmacoeconomic evaluation, drug costs, quality of life, and indicators of oxidative stress. The treatment will last for 24 weeks with a follow-up visit at baseline (within 7 days prior to initial treatment) and weeks 4, 8, 12, 16, 20, and 24 after initial treatment. This clinical research includes 9 hemodialysis centers in mainland China and plans to enroll 186 participants.Discussion: It is expected that it will provide strong evidence to reveal the clinical efficacy and safety of oral iron in the treatment of chronic CKD-related anemia in MHD patients through this clinical trial.Trial Registration: Chinese Clinical Trial Registry ChiCTR2000031166 . Registered on March 23, 2020. [ABSTRACT FROM AUTHOR]

Studying the mechanisms of the spin Hall effect (SHE) is essential for the fundamental understanding of spintronic physics. By now, despite the intensive studies of SHE on heavy metal (HM)/metallic magnet heterostructures, the SHE on HM/ferrimagnetic insulator (FMI) heterostructures still remains elusive. Here, we study the mechanism of SHE in the Pt/Tm 3 Fe 5 O 12 (TmIG) heterostructure. We first tune the crystallinity and resistivity of Pt by an annealing method, and then study the spin–orbit torque (SOT) in the tuned-Pt/TmIG devices. The SOT generation efficiency per unit electric field and spin Hall angle were obtained, which are insensitive to the annealing temperature. We further demonstrate that the intrinsic contribution in the moderately dirty regime is responsible for the SHE in our Pt/TmIG bilayer. Our study provides an important piece of information for the SHE in FMI-based spintronic physics. [ABSTRACT FROM AUTHOR]

Fabric-based electromagnetic wave (EMW) absorption materials are desirable owing to their inherent flexibility, cost-effectiveness, and easily conformable lightweight structures. However, the problems such as high density and susceptibility to abrasion limit their applications and service life. Herein, flexible fabric-based EMW absorption material (FEMWAM) were prepared by a multiscale synergistic approach. At the microscopic scale, CF@NiCo 2 O 4 @MnO 2 absorbents with enhanced impedance matching and interfacial polarization are prepared by solvent method and hydrothermal process. The influence of heterostructure on the electromagnetic response is also examined. At the macroscopic scale, flexible FEMWAM are prepared by freeze-drying. The electromagnetic parameters of FEMWAM was effectively regulated by altering the amount of the CF@NiCo 2 O 4 @MnO 2 absorbents, which achieve excellent EMW absorption performance and thermal insulation property while maintaining flexibility. The minimal reflection loss (RL min) of −27.8 dB can be achieved at a thickness of 2.70 mm, and an EAB covering the complete X-band can be obtained when the thickness is in the range of 3.20–3.26 mm. The large thickness range provides convenience for the control of dimensional accuracy in actual production, so as to better adapt to practical applications. These findings provide effective guidance for the preparation of EMW absorption materials with excellent flexibility, thermal insulation properties and absorption performance. [Display omitted] [ABSTRACT FROM AUTHOR]

Ionisable amino‐lipid is a key component in lipid nanoparticles (LNPs), which plays a crucial role in the encapsulation of RNA molecules, allowing efficient cellular uptake and then releasing RNA from acidic endosomes. Herein, we present direct evidence for the remarkable structural transitions, with decreasing membrane curvature, including from inverse micellar, to inverse hexagonal, to two distinct inverse bicontinuous cubic, and finally to a lamellar phase for the two mainstream COVID‐19 vaccine ionisable ALC‐0315 and SM‐102 lipids, occurring upon gradual acidification as encountered in endosomes. The millisecond kinetic growth of the inverse cubic and hexagonal structures and the evolution of the ordered structural formation upon ionisable lipid‐RNA/DNA complexation are quantitatively revealed by in situ synchrotron radiation time‐resolved small angle X‐ray scattering coupled with rapid flow mixing. We found that the final self‐assembled structural identity, and the formation kinetics, were controlled by the ionisable lipid molecular structure, acidic bulk environment, lipid compositions, and nucleic acid molecular structure/size. The implicated link between the inverse membrane curvature of LNP and LNP endosomal escape helps future optimisation of ionisable lipids and LNP engineering for RNA and gene delivery. [ABSTRACT FROM AUTHOR]

Ionisable amino‐lipid is a key component in lipid nanoparticles (LNPs), which plays a crucial role in the encapsulation of RNA molecules, allowing efficient cellular uptake and then releasing RNA from acidic endosomes. Herein, we present direct evidence for the remarkable structural transitions, with decreasing membrane curvature, including from inverse micellar, to inverse hexagonal, to two distinct inverse bicontinuous cubic, and finally to a lamellar phase for the two mainstream COVID‐19 vaccine ionisable ALC‐0315 and SM‐102 lipids, occurring upon gradual acidification as encountered in endosomes. The millisecond kinetic growth of the inverse cubic and hexagonal structures and the evolution of the ordered structural formation upon ionisable lipid‐RNA/DNA complexation are quantitatively revealed by in situ synchrotron radiation time‐resolved small angle X‐ray scattering coupled with rapid flow mixing. We found that the final self‐assembled structural identity, and the formation kinetics, were controlled by the ionisable lipid molecular structure, acidic bulk environment, lipid compositions, and nucleic acid molecular structure/size. The implicated link between the inverse membrane curvature of LNP and LNP endosomal escape helps future optimisation of ionisable lipids and LNP engineering for RNA and gene delivery. [ABSTRACT FROM AUTHOR]

Although the hot-casting (HC) method can obtain efficient quasi-2D perovskite solar cells, this method cannot effectively control the uniformity of the thin film, and the high preheating substrate temperature will also form low n perovskite phases (n = 2) at the interface, which is not conducive to the transport of carriers. Semitransparent solar cells have great application prospects in building-integrated photovoltaic and tandem devices. Herein, a non-preheating (NP) film-casting method is proposed to realize a highly uniform and phase controllable quasi-2D perovskite film (BA2MA3Pb4I13, BA+:C4H11NH3+, MA+:CH3NH3+). As a result, the NP-processed film gets the highest light utilization efficiency (LUE = 4.01%) for semitransparent quasi-2D perovskite solar cells (ST-Quasi-2D-PSCs) with power conversion efficiency (PCE) of 9.60%, average visible transmittance (AVT) of 41.73%, good bifaciality factor, high LUE in low light intensity and good stability. [ABSTRACT FROM AUTHOR]

This article, published in Small Science, discusses the development of ionizable lipid cubosomes as a delivery system for antimicrobial agents. The cubosomes, composed of monoolein, ionizable cationic lipid ALC-0315, and ionizable anionic oleic acid, have an internal inverse cubic structure that enhances the membrane permeability of piperacillin-loaded particles. This leads to increased inhibition of Gram-negative bacteria growth. The research was conducted by Haitao Yu, Calum J. Drummond, Jiali Zhai, and their colleagues. [Extracted from the article]

Rheumatoid arthritis is a chronic systemic autoimmune disease. In this study, the role of microRNA-340-5p in rheumatoid arthritis was investigated. qRT-PCR was used to detect the expression of microRNA-340-5p in serums, synovial tissues, and fibroblast-like synoviocytes from patients and healthy participants. Cell proliferation rate, cell cycle and apoptotic cell numbers were measured by CCK-8 and flow cytometry assays. The expression of pro-inflammation factors was determined by ELISA. Our data showed that the expression of microRNA-340-5p was greatly suppressed in rheumatoid arthritis serums, synovial tissues and rheumatoid arthritis-fibroblast-like synoviocytes compared to that in healthy controls. Over-expression of microRNA-340-5p greatly suppressed cell proliferation, promoted cell apoptosis, and suppressed the expression of inflammation factors in rheumatoid arthritis fibroblast-like synoviocytes. Additionally, STAT3 was a target of microRNA-340-5. Overexpression of STAT3 could reverse the outcome of microRNA-340-5p on cell proliferation and apoptosis in rheumatoid arthritis fibroblast-like synoviocytes. The findings in our study demonstrated that microRNA-340-5p may serve as a potential target for therapeutic direction for patients with rheumatoid arthritis. [ABSTRACT FROM AUTHOR]

In rheumatoid arthritis (RA), fibroblast-like synoviocytes (FLSs) play an essential role in cartilage destruction. Aggressive migration and invasion by FLSs significantly affect RA pathology. Kaempferol has been shown to inhibit cancer cell migration and invasion. However, the effects of kaempferol on RA FLSs have not been investigated. Our study aimed to determine the effects of kaempferol on RA both in vitro and in vivo. In vitro, cell migration and invasion were measured using scratch assays and the Boyden chamber method, respectively. The cytoskeletal reorganization of RA FLSs was evaluated by immunofluorescence staining. Matrix metalloproteinase (MMP) levels were measured by real-time PCR, and protein expression levels were measured by western blotting. In vivo, the effects of kaempferol were evaluated in mice with CIA. The results showed that kaempferol reduced migration, invasion and MMP expression in RA FLSs. In addition, we demonstrated that kaempferol inhibited reorganization of the actin cytoskeleton during cell migration. Moreover, kaempferol dramatically suppressed tumor necrosis factor (TNF)-α-induced MAPK activation without affecting the expression of TNF-α receptors. We also demonstrated that kaempferol attenuated the severity of arthritis in mice with CIA. Taken together, these results suggested that kaempferol inhibits the migration and invasion of FLSs in RA by blocking MAPK pathway activation without affecting the expression of TNF-α receptors. [ABSTRACT FROM AUTHOR]

Accurately detect vehicles or pedestrians from 3D point clouds (3D object detection) is a fast developing research topic in autonomous driving and other domains. The fundamental component for feature extraction in 3D object detection is Set Abstraction (SA), which can downsample points while aggregating points to extract features. However, the current SA ignores the geometric and semantic properties of point clouds and may miss to detect remote small objects. In this paper, FocusSA is proposed, which consists two modules for enhancing useful feature extraction in the SA layer to improve 3D object detection accuracy. At first, Focused FPS (FocFPS) is proposed to evaluate the foreground and boundary scores of the points and reweighs the Furthest Point Sampling (FPS) using the evaluated scores to retain more contextual points in downsampling. Then a Geometry-aware Feature Extraction (GeoFE) module is proposed to add geometric information to enrich the awareness of geometric structure in feature aggregation. To evaluate the performances of the proposed methods, we conduct extensive experiments on three difficulty levels of Car class in KITTI dataset. The experimental results show that on "moderate" instances, our results outperform the state-of-the-art method by 1.08%. Moreover, FocusSA is easy to be plugged in popular architectures. [ABSTRACT FROM AUTHOR]

The Alpha Magnetic Spectrometer (AMS) is constantly exposed to harsh condition on the ISS. As such, there is a need to constantly monitor and perform adjustments to ensure the AMS operates safely and efficiently. With the addition of the Upgraded Tracker Thermal Pump System, the legacy monitoring interface was no longer suitable for use. This paper describes the new AMS Monitoring Interface (AMI). The AMI is built with state-of-the-art time series database and analytics software. It uses a custom feeder program to process AMS Raw Data as time series data points, feeds them into InfluxDB databases, and uses Grafana as a visualization tool. It follows modern design principles, allowing client CPUs to handle the processing work, distributed creation of AMI dashboards, and up-to-date security protocols. In addition, it offers a more simple way of modifying the AMI and allows the use of APIs to automate backup and synchronization. The new AMI has been in use since January 2020 and was a crucial component in remote shift taking during the COVID-19 pandemic. • Alpha Magnetic Spectrometer monitoring data. • Time series database. • Time series data analytics. • New Monitoring Interface. • Grafana. [ABSTRACT FROM AUTHOR]

[Display omitted] • CF@MnO 2 composites with controllable structure were prepared by a facile hydrothermal method. • The growth process of MnO 2 was studied. • The effect of micro morphology on electromagnetic wave absorption performance was studied. Recently, electromagnetic wave (EMW) absorption materials with enhanced and tunable EMW absorption performance are required in practical applications, and attaining such performance by a simple method remains a vital challenge. In this study, manganese dioxide (MnO 2) with controllable structures were vertically grown on carbon fibers (CF) through a hydrothermal method. The sheet-like (CF@MnO 2 -NS) and wire-like (CF@MnO 2 -NW) structures were obtained by merely adjusting the solution chemistries ([K+] and [H+]) and reaction time. The wire-like structure exhibited high attenuation capability due to a larger specific surface area and dielectric resonance, but exhibited a relatively poor impedance matching ratio resulting in inferior EMW absorption performance at low frequencies. However, the sheet-like structure exhibited better EMW absorption performance overall. The minimum reflection loss (RL min) value of CF@MnO 2 -NS and CF@MnO 2 -NW reached −56.6 dB and −52.9 dB, respectively. Additionally, the EMW absorption performance varies with frequency. CF@MnO 2 -NW performed better in the X-band, while CF@MnO 2 -NS achieved an excellent performance in the C-band. This study provides a simple approach for designing EMW absorption materials with controllable morphologies and for realizing tunable EMW performances. [ABSTRACT FROM AUTHOR]

Abstract: Al–TiO2–Fe–Fe2O3–MnO2, as the main reaction system, was selected to prepare the agglomerate powders containing energy (APCE) on 50–90μm by balling, drying, carbonating, grinding and sieving. Self-reactive quenching technology, which is integrated with flame spraying, self-propagating high-temperature synthesis (SHS) and rapid solidification, was used to spray and melt the APCE. Flight combustion of the APCE was analyzed by high-speed photography, water quenching, collisions and Gibbs free energy graph, and surface morphologies of quenching products were characterized by SEM. The results show that the APCE goes through three stages, which mean heat storage (0–80mm, 66–72ms), heat releasing (80–240mm, 73–83ms) and after combustion (240–400mm, 84–99ms), to form hollow ceramic droplets which decisively affect the quality of hollow multiphase ceramic microspheres. Collisions and burst may be the main reasons to produce flame retrogression and affect the particle size distribution of hollow multiphase ceramic microspheres simultaneously. [Copyright &y& Elsevier]

Fe-Fe2O3-BaCO3-sucrose-epoxy resin and O2 as reaction system and feeding gas, respectively, were used to prepare M-type BaFe12O19 hollow ceramic microspheres (BaM HCMs) absorbent by self-reactive quenching technology which combines flame thermal spraying, self-propagating high temperature synthesis (SHS), and rapidly solidification. The morphologies and phase composition before and after heat treatment of HCMs were studied by SEM, XRD, and EDS, and microwave absorption properties were also analyzed. The results showed that before heat treatment, the phase was composed of Fe3O4, Fe2O3, BaFe2O4, and BaCO3. And thick dendrite, eutectic of dendrite and amorphous and amorphous were formed on the surface of HCMs. After heat treatment, high purity single BaM HCMs was obtained, and the surface was transformed into nanolamella, micro-nano isometric grain, eutectic of nanolamella and isometric grain, and hexagonal crystal. Absorption test result showed that at 0.5-18 GHz, both ε′ and ε″ of HCMs reduced obviously, but the μ″ increased by heat treatment. Therefore, the minimum reflectivity and bandwidth less than −10 dB were improved to −22.1 dB and 5.7 GHz (12.3-18 GHz), respectively. The improvement of electromagnetic match resulted by obvious reduction of permittivity, and the magnetocrystalline anisotropy, shape anisotropy, and various polarizations generated from special surface morphologies may be the main reasons to make microwave absorption properties better. [ABSTRACT FROM AUTHOR]

Wurtzite-type Zn 0.96 Co 0.04 O nanotubes are prepared through coaxial electrospinning technology and heat-treatment for 2 h at 600, 700 and 800 °C. The phases, morphology, microwave absorption properties and infrared emissivity are investigated by TGA, XRD, SEM, TEM, vector network analyzer and a IR-2 infrared emissivity tester respectively. The results show that pure wurtzite-type Zn 0.96 Co 0.04 O is formed at 600 °C and above. As the heat-treatment temperature increas, Zn 0.96 Co 0.04 O exhibit the morphology of hollow tubes, short nanotubes and irregular nanoparticles. Dielectric loss is the main loss mechanism of Zn 0.96 Co 0.04 O nanotubes. The matching thickness of Zn 0.96 Co 0.04 O nanotubes is 2 mm, at which the microwave absorption properties are fine. The minimum reflectivity is −20.3 dB at 9.5 GHz, and the effective absorption frequency band less than −10 dB is 8.4–12.0 GHz, with the bandwidth of 3.6 GHz. The average infrared emissivity value of Zn 0.96 Co 0.04 O nanotubes is 0.72. • In this work, wurtzite-type Zn 0.96 Co 0.04 O nanotubes are prepared through coaxial electrospinning technology and heat-treatment. The effects of heat-treatment on morphology and hollow morphology on the microwave absorbing properties and infrared emissivity are mainly investigated. • As the temperature increas, Zn 0.96 Co 0.04 O exhibit the morphology of hollow tubes, short nanotubes and irregular nanoparticles. • Dielectric loss is the main loss mechanism of Zn 0.96 Co 0.04 O nanotubes. The matching thickness of Zn 0.96 Co 0.04 O nanotubes is 2 mm, at which the microwave absorption properties are fine. The minimum reflectivity is −20.3 dB at 9.5 GHz, and the effective absorption frequency band less than −10 dB is 8.4–12.0 GHz. • The average infrared emissivity value of Zn 0.96 Co 0.04 O nanotubes is 0.72. Nanotubes has can reduce the transfer and absorption of infrared radiation energy. [ABSTRACT FROM AUTHOR]