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Summary: Additive engineering has become increasingly important for making high-quality perovskite solar cells (PSCs), with a recent example involving acid during fabrication of cesium-based perovskites. Lately, it has been suggested that this process would introduce dimethylammonium ((CH3)2NH2+, DMA+) through hydrolysis of the organic solvent. However, material composition of the hydrolyzed product and its effect on the device performance remain to be understood. Here, we present an in-depth investigation of the hydrolysis-derived material (i.e., DMAPbI3) and detailed analysis of its role in producing high-quality PSCs. By varying the ratio of CsI/DMAPbI3 in the precursor, we achieve high-quality CsxDMA1-xPbI3 perovskite films with uniform morphology, low density of trap states, and good stability, leading to optimized power conversion efficiency up to 14.3%, with over 85% of the initial efficiency retained after ∼20 days in air without encapsulation. Our findings offer new insights into producing high-quality Cs-based perovskite materials. : Energy Sustainability; Materials Characterization; Energy Materials Subject Areas: Energy Sustainability, Materials Characterization, Energy Materials

Structural instability and limited operational efficiency of sodium-ion battery (SIB) anodes, compared lithium-ion battery (LIB) anodes, are main hurdles for their large-scale applications that can be tackled using self-tunable electrode materials. Here, we created and utilized ultrathin partially-crystalline carbon nanocups (CNCs) that have the ability to self-tune their structure, contain highly tangled walls and present open framework for enhanced energy densities for SIBs and the outcomes are benchmarked with LIBs. The tangled wall structure offers enhanced spacings for ionic storage and the open framework supports enhanced mass transport, while partial-crystallinity of CNCs provides high conductivity and stabilizes the structure for long cycle life. The CNCs delivered high capacities up to 468 mAh/g for SIBs at 25 mA/g and 953 mAh/g for LIBs at 50 mA/g after 100 cycles, respectively, while bore excellent stability by delivering highly stable performance exceeding 1000 cycles for SIBs at 1.5 A/g and 5000 cycles for LIBs at 7.5 A/g (20 C) with only a loss of 0.013 mAh/g per cycle. Moreover, when tested in lower voltage ranges, the CNCs delivered unprecedented capacity of 368 mAh/g (0.01–2.0 V) for SIBs and 671 mAh/g (0.01–2.0 V) and 449 mAh/g (0.01–1.5 V) for LIBs at 25 and 50 mA/g, respectively, which indicate the usability of the CNCs in full-cells. The post-electrochemical characterizations revealed that the developed CNCs self-modified their interlayer spacings (average spacing increased to 0.44 nm from 0.42 nm) during charge-discharge to create additional voids for increased ionic storage and stable performance, especially for Na+, while maintaining their overall morphology, composition and structure. The structural design presented here will provide new pathways of tailoring carbonaceous nanostructures for future high-performance energy storage devices.

Most microwave absorbers lose their function under harsh working conditions, such as a high temperature and an oxidative environment. Here, we developed a heterogeneous ZrN0.4B0.6/SiC nanohybrid via combined catalytic chemical vapor deposition (CCVD) and chemical vapor infiltration (CVI) processes using ZrB2 as the starting material. The composition and structure of the ZrN0.4B0.6/SiC nanohybrid were controlled by tuning the CCVD and CVI parameters, such as reaction temperature, time, and reactant concentration. The optimal heterogeneous ZrN0.4B0.6/SiC nanohybrids were obtained initially by preparing ZrB2@C via the CCVD process at 650 °C for 30 min and the subsequent CVI at 1500 °C, where the ZrB2@C reacted with Si under N2. The ZrN0.4B0.6/SiC nanohybrid exhibited enhanced microwave absorption ability with a minimum reflection loss value of approximately -50.8 dB at 7.7 GHz, a thickness of ∼3.05 mm, and antioxidation features at a high temperature of 600 °C. The heterogeneous ZrN0.4B0.6/SiC nanohybrid possessed reasonable conductivity, leading to dielectric loss, whereas SiC nanofibers formed a three-dimensional network that brought higher dipole moments, whereas a small part of the ZrN0.4B0.6/SiC nanohybrid structure generated an effective interface for higher attenuation of microwaves. Therefore, these material features synergistically resulted in a well-defined Debye relaxation, Maxwell-Wagner relaxation, dipole polarization, and the quarter-wavelength cancellation, which accounted for the enhanced microwave absorption.

ZrB2-based ceramics with different microstructures were prepared through different processes. Electrical resistivity of all samples was measured under vacuum environment by four-probe method over temperature range from 50 to 1000 °C. It was found that electrical resistivity and internal interface electrical resistivity of all samples increased linearly with environmental temperature. All samples showed nearly equal values of α, which was calculated using the formula: ρ(T1) = ρ(T0)+α·ρ(T0)·(T1-T0). This might be due to the fact that ZrB2 acted as electrical conductive phase in all samples. The relationship between electrical properties and microstructure of ZrB2-based ceramics was investigated. Increase in volume fraction of insulating phase and increase in internal interface electrical resistance can both cause effective electrical resistivity of ZrB2-based ceramics to increase. Internal interface electrical resistance was influenced by oxide impurities on the surface of ZrB2 particles and average particle size of ZrB2 particles.

Because of high color saturation and fewer layers, metal-dielectric thin film has been used for years in the field of special effect coatings such as security and decorative applications. In the application of red color, purple red and orange red metal-dielectric thin films have already been realized, however, pure red thin film has not been achieved. In this paper, color target optimization method is adopted to eliminate the blue second order reflect peak (460 nm–470 nm) and compress the red first order reflect peak (675 nm), consequently, a seven-layer metal-dielectric pure red thin film is designed and fabricated. The chromaticity coordinate is (x,y) = (0.635,0.32) at normal incidence, which is located in pure red region, and the gold color target coordinate is (x,y) = (0.52,0.45) at 45°. The final base structure is Air/1.5Cr/230SiO2/6.3Cr/225SiO2/8.9Cr/213SiO2/100Al/Glass, where the numbers refer to layer thicknesses in nanometers. As the observation angle is increased from 0° to 45°, the thin film varies from pure red to gold. Remote plasma sputtering technique is used to fabricate the multilayer thin film. Finally, pure red thin films are demonstrated for the automobile coatings and optically variable ink applications, and the practical color effects are presented.

Current study aimed at investigating oxidation behaviour of plasma-sprayed ZrB2-SiC coatings, which were deposited using different spray powers. Moreover, oxidation tests were carried out within temperature range of 400–1200 °C. Results from X-ray powder diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy (EDS) suggested that ZrB2-SiC coatings had been markedly oxidized at 600 °C. Besides, oxidation behaviour of ZrB2-SiC block ceramics, which had achieved different densities using spark plasma sintering (SPS) and pressureless sintering (PS), was also studied to explain oxidation behaviour of plasma-sprayed ZrB2-SiC coatings. Results revealed that high-density ZrB2-SiC block ceramics displayed better oxidation resistance than low-density counterparts, indicating that unfavorable oxidation resistance of ZrB2-SiC coatings could be ascribed to low density, since there were more pores in ZrB2-SiC coatings, which provided channels for oxygen diffusion.

The effective treatment of industrial wastewater to protect freshwater reserves for the survival of life is a primary focus of current research. Herein, a multicomponent Eleocharis-manganese peroxidase enzyme (Eleocharis@MnPE) layered hybrid with high surface area (1200 m2/m3), with a strong synergistic adsorption and catalytic biodegradation (SACB), has been developed through a facile method. A combination of outer porous (Eleocharis) and inner catalytically active (MnPE) components of the hybrid resulted in highly efficient SACB system, evidenced by high removal rate of 15 kg m-3 day-1 (100%) and complete degradation of toxic Orange II (OR) azo dye into nontoxic products (gases and weak acids). The Eleocharis@MnPE layered hybrid efficiently degraded both OR in synthetic wastewater and also other azo dyes (red, pink, and yellow dyes) present in three different textile industrial effluents. For the industrial effluents, these were evidenced by the color disappearance and reduction in biological oxygen demand (BOD), chemical oxygen demand (COD), and total organic carbon (TOC) of up to 97%, 92%, and 76%, respectively. Furthermore, reduced toxicity of treated wastewater was confirmed by decreased cell toxicity to 0.1%-1% and increased cell viability to 90%. We believe that designing a hybrid system with strong ability of SACB could be highly effective for industrial-scale treatment of wastewater.

The tensile strength measured by Brazilian test is termed the splitting tensile strength. The values of splitting tensile strength and corresponding strain may be affected by loading and/or strain rates used in the Brazilian test. In order to investigate the effects, several Brazilian tests with two-type loading modes were carried out. One is under a constant loading rate (BT-CLR), and the other is under a constant strain rate (BT-CSR). Lightly weathered sandstone and mudstone are selected as test materials. Experimental data indicate that, while the loading rate increases from 0.3 to 0.5 MPa/s, the splitting tensile strengths of sandstone and mudstone are increasing about 12.2% and 16.0%, respectively. With increasing the strain rate from 0.005 to 0.02 mm/s, the splitting tensile strengths of sandstone and mudstone increase about 9.3% and 12.8%, respectively. With increment of loading and/or strain rate, the critical strains of both sandstone and mudstone decrease. The effect degree, in percentage, on the mudstone is greater than one on the sandstone.

Development of high-performance materials for electromagnetic wave absorption has attracted extensive interest, but it still remains a huge challenge especially in reducing density and lowering filler loading. Herein, a hierarchical all-carbon nanostructure is rationally designed as follows: the defect-rich hollow graphite capsules (GCs) controlled by the size/density of ZnO templates are synthesized on the surface of helical carbon nanotubes (HCNTs) to form a hybrid nanocomposite, denoted as GCs@HCNTs. As a result, the GCs@HCNTs demonstrate a strong and wide absorption performance with a very low filler loading of 10 wt %. The minimum reflection loss reaches -51.7 dB at 7.6 GHz, and the effective bandwidth (below -10 dB) ranges from 8 to 14 GHz, covering the whole X or Ku bands. The hierarchical nanostructure and homoatomic heterogeneous interface are beneficial to impedance matching and bring additional dipole polarization enhanced by the structural defects, which may enlighten the design of ultralight and broadband high-performance electromagnetic wave absorption materials.

The cryptocurrency economy provides a comprehensive digital trace of human economic behavior: almost all cryptocurrency users’ activities are faithfully recorded in transactions on public blockchains. However, the user identifiers in the transaction records, i.e., blockchain addresses, are anonymous. That is, they cannot be associated with any real “off-chain” identify of actual users. Nonetheless, identifying the economic roles of the addresses from their past behaviors is still feasible. This paper analyzes Ethereum token transactions, characterizes key economic agents’ behavior from their transaction patterns, and explores their identifiability through interpretable machine learning models. Specifically, six types of most active economic agents are considered, including centralized cryptocurrency exchanges, decentralized exchanges, cryptocurrency wallets, token issuers, airdrop services, and gaming services. Transaction patterns such as trading volume, transaction tempo, and structural properties of transaction networks are defined for individual blockchain addresses. The results showed that cryptocurrency exchanges and online wallets have signature behavior patterns and hence can be accurately distinguished from other agents. Token issuers, airdrop services, and gaming services can sometimes be confused. Moreover, transaction networks’ features provide the richest information in the economic agent’s identification.

Continuous fluorine (F) accumulation in soil by anthropogenic activities leads to variously global environmental and health issues. Herein, 300 farmland soil samples were collected from different anthropogenic activity dominated districts for studying the distribution and related health risk of F in soils. Co-existing metal concentrations in soil samples were also analysed to evaluate the relationship between the distribution of F and metals in soil. The median value of the total F concentration of 488 mg kg

Activated microglia can suppress neurite outgrowth and synapse recovery in the acute stage following traumatic brain injury (TBI). However, the underlying mechanism has not been clearly elucidated. Exosomes derived from microglia have been reported to play a critical role in microglia-neuron interaction in healthy and pathological brains. Here, we aimed to investigate the role of microglia-derived exosomes in regulating neurite outgrowth and synapse recovery following TBI. In our study, exosomes derived from microglia were co-cultured with stretch-injured neurons in vitro and intravenously injected into mice that underwent fluid percussion injury (FPI) by tail vein injection in vivo. The results showed that microglia-derived exosomes could be absorbed by neurons in vitro and in vivo. Moreover, exosomes derived from stretch-injured microglia decreased the protein levels of GAP43, PSD-95, GluR1, and Synaptophysin and dendritic complexity in stretch-injured neurons in vitro, and reduced GAP43+ NEUN cell percentage and apical dendritic spine density in the pericontusion region in vivo. Motor coordination was also impaired in mice treated with stretch-injured microglia-derived exosomes after FPI. A microRNA microarray showed that the level of miR-5121 was decreased most greatly in exosomes derived from stretch-injured microglia. Overexpression of miR-5121 in stretch-injured microglia-derived exosomes partly reversed the suppression of neurite outgrowth and synapse recovery of neurons both in vitro and in vivo. Moreover, motor coordination in miR-5121 overexpressed exosomes treated mice was significantly improved after FPI. Following mechanistic study demonstrated that miR-5121 might promote neurite outgrowth and synapse recovery by directly targeting RGMa. In conclusion, our finding revealed a novel exosome-mediated mechanism of microglia-neuron interaction that suppressed neurite outgrowth and synapse recovery of neurons following TBI. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13311-020-00999-z.

Additional file 1. Additional tables and figures.

The Toushe Basin in central Taiwan is a local tourist attraction. Because the local dense fog often traps tourists in it, the main research purpose of this paper is to solve the problem of dense fog detection. Because the edge characteristics of fog images will disappear with the increase of fog concentration, analysis The proportion of the image that the edge occupies is used as the basis for fog concentration. In addition, the characteristic that the chroma of the image decreases as the fog concentration increases is used to convert the image to histogram, and the fog concentration is determined by analyzing the histogram of the image. In order to be more in line with the local fog in the Toshe Basin, the fog film data collection used in this paper is all taken on-site. The two fog concentration methods proposed in this paper are not only effective for analyzing the local area of the Toshe Basin. In addition to the fog concentration, it can also be used in places where various fogs are often generated after the threshold is adjusted.

Antireflection (AR) coatings allow increased substrate transmission and reduce surface reflection over a specific wavelength range. We proposed a blue-blocking (BB) AR coating that allows maximal visible-light transmittance while minimizing the transmittance of blue light, owing to selective absorption. Admittance diagrams of BB Cr2O3 / SiO2 coatings and traditional AR Ta2O5 / SiO2 coatings were shown to demonstrate that small absorption affects the reflectance much less than it affects the transmittance. Therefore, by controlling the degree of absorption, the lower residual reflection can be obtained by optimizing the thickness of different layers of the overall stacked structure. Coatings were fabricated using remote plasma sputtering to meet the requirements of low residual reflectance (

Background Glioblastoma multiforme, the most aggressive and malignant primary brain tumor, is characterized by rapid growth and extensive infiltration to neighboring normal brain parenchyma. Our previous studies delineated a crosstalk between PI3K/Akt and JNK signaling pathways, and a moderate anti-glioblastoma synergism caused by the combined inhibition of PI3K p110β (PI3Kβ) isoform and JNK. However, this combination strategy is not potent enough. MLK3, an upstream regulator of ERK and JNK, may replace JNK to exert stronger synergism with PI3Kβ. Methods To develop a new combination strategy with stronger synergism, the expression pattern and roles of MLK3 in glioblastoma patient’s specimens and cell lines were firstly investigated. Then glioblastoma cells and xenografts in nude mice were treated with the PI3Kβ inhibitor AZD6482 and the MLK3 inhibitor URMC-099 alone or in combination to evaluate their combination effects on tumor cell growth and motility. The combination effects on cytoskeletal structures such as lamellipodia and focal adhesions were also evaluated. Results MLK3 protein was overexpressed in both newly diagnosed and relapsing glioblastoma patients’ specimens. Silencing of MLK3 using siRNA duplexes significantly suppressed migration and invasion, but promoted attachment of glioblastoma cells. Combined inhibition of PI3Kβ and MLK3 exhibited synergistic inhibitory effects on glioblastoma cell proliferation, migration and invasion, as well as the formation of lamellipodia and focal adhesions. Furthermore, combination of AZD6482 and URMC-099 effectively decreased glioblastoma xenograft growth in nude mice. Glioblastoma cells treated with this drug combination showed reduced phosphorylation of Akt and ERK, and decreased protein expression of ROCK2 and Zyxin. Conclusion Taken together, combination of AZD6482 and URMC-099 showed strong synergistic anti-tumor effects on glioblastoma in vitro and in vivo. Our findings suggest that combined inhibition of PI3Kβ and MLK3 may serve as an attractive therapeutic approach for glioblastoma multiforme.

quot;Huajiaoquot; is dried ripe fruit peel of Zanthoxylum bungeanum or Z. schinifolium, is konwn as geoherbs, especially thequot;Dahongpaoquot; cultivated in Hanyuan, Maoxian and Jiulong of Sichuan province. However, the genetic basis of Dao-diquot;Huajiaoquot; is virtually unknown. The transcriptome of the fruit and leaf from Sichuan(Hanyuan, Jiulong, Lixian, Maoxian), Gansu(Wudu) province and Shaanxi(Fengxian) province was sequenced. Trinity de novo assembling resulted in a total of 177 616 unigenes. Through the KEGG, NR, SwissProt, Trembl, KOG/COG, GO, Pfam database comparision 106 644 annotated Unigene finally, 4 574 deferentially expressed genes were found in fruit between Sichuan and other provinces, including 3 740 up-regulated genes and 834 down-regulated genes. Among the up-regulated genes, 27 up-regulated genes were raleted to terpenoids, and 8 up-regulated genes were related to isoquinoline alkaloid bio-synthesis. Furthermore, it was also showed remarkable differences in groups which enrichment ratio of the diffe-rent expressed gene compared. The different expressed genes were annotated by the KEGG database into plant-pathogen interaction, plant hormone signal transduction and phenylpropanoid biosynthesis in fruit and leaf, but isoflavonoid bio-synthesis and betaine bio-synthesis were significantly different in fruit and leaf. The study laid a certain reference basis for comparison of quality and different expressed gene of Z. bungeanum from different groups.

Supplementary_materials for SLC6A8 Knockdown Suppresses the Invasion and Migration of Human Hepatocellular Carcinoma Huh-7 and Hep3B Cells by Lu Yuan, Xian Jian Wu, Wen Chuan Li, Chenyi Zhuo, ZuoMing Xu, Chuan Tan, RiHai Ma, JianChu Wang and Jian Pu in Technology in Cancer Research & Treatment

Chronic subdural hematoma (CSDH) is a common neurological disease that involves the collection of blood products in the subdural space. The progression of CSDH is an angiogenic and inflammatory process, but the multifactorial mechanisms underlying CSDH are still not fully understood. We aimed to identify one or more factors that may play an important role in the development of CSDH. We enrolled 83 patients with CSDH, including 17 postoperative patients, and analyzed 20 markers in the hematoma fluid and peripheral blood of each patient. Overall differential gene expression was examined to identify the representative markers. The concentration of MMP-8 was significantly lower in the postoperative group than in the preoperative group. The concentration of MMP-9 was significantly higher in the postoperative group than in the preoperative group. These findings indicate that MMP-8 and MMP-9 may play important roles in the pathophysiology of CSDH. Understanding the pathways associated with CSDH may provide insights for improving disease outcomes.

Li/CFx batteries are widely applied in medical and electronic products because of their outstanding electrochemical performance. However, the poor intrinsic conductivity and inevitable polarization of the CFx material result in low ion migration and rate performance. Herein, an ultraviolet (UV)-radiation inducing technology to adjust the C–F bonding types, which improved the rate performance of the Li/CFx battery. UV radiations reasonably change the ratio of various C–F bonds, namely, not only increased the concentration of semi-ionic C–F bonds, but also reduced the relative proportion of inert C–F2 and inactive C–F3. Then this technology further increases the conductivity of the CFx and improves the rate performance of Li/CFx batteries. After UV-modification, the CFx possesses more multi-level channels to favor the electrolyte infiltration, shortening the charge transmission distance. And the in situ formed carbon coating also contributes to the enhanced conductivity. Compared with the original FSC losing the discharge capacity at 1 C, the optimal FSC-5W-72h has a specific capacity of 762.1 mAh/g and a specific energy of 1615.4 Wh/kg at 1 C. This UV radiation technology has created a novel way to address the reasonable C–F bonds of CFx and in-situ carbon coating, improving the rate performance of Li/CFx battery.

Exploring efficient microwave absorbers at high temperature is a hot topic in the practical application. Non-isothermal oxidation kinetics of FeSiAl alloy powder sized of ∼45 μm were investigated by thermogravimetry analysis (TG) and differential scanning calorimetry (DSC) under linear temperature control program (ranging from 30 to 1200 °C) at different heating rates (5, 10, 15, 20 and 25 K/min) in air. It can be found that the melt point of FeSiAl alloy powder is about 1165 °C. The oxidation of FeSiAl alloy powder can be divided into two stages including solid-oxidation stage (before melting) and liquid oxidation stage (after melting). Non-isothermal kinetic analysis of oxidation of FeSiAl alloy powder were performed by using Flynn-Wall-Ozawa (FWO) method. Besides, the surface morphology of particles present a smooth trend by scanning electron microscope. And the microwave absorption performance of FeSiAl alloy powder is confirmed to be a good potential candidate in case of high temperature with the lowest refection loss value of −25.14 dB and effective absorbing bandwidth in range of 4–18 GHz adjusting the thickness.

The oxidative degradation of ZrB2 ceramics is the main challenge for its extensive application under high temperature condition. Here, we report an effective method for co-doping suitable compounds into ZrB2 in order to significantly improve its anti-oxidation performance. The incorporation of SiC and WC into ZrB2 matrix is achieved using spark plasma sintering (SPS) at 1800 °C. The oxidation behavior of ZrB2-based ceramics is investigated in the temperature range of 1000 °C–1600 °C. The oxidation resistance of single SiC-doped ZrB2 ceramics is improved due to the formation of silica layer on the surface of the ceramics. As for the WC-doped ZrB2, a dense ZrO2 layer is formed which enhances the oxidation resistance. Notably, the SiC and WC co-doped ZrB2 ceramics with relative density of almost 100% exhibit the lowest oxidation weight gain in the process of oxidation treatment. Consequently, the co-doped ZrB2 ceramics have the highest oxidation resistance among all the samples.

The application of composites of carbon matrix and ferromagnetic nanoparticles as electromagnetic wave absorption materials has received extensive attention. In this study, we successful synthesized metal organic framework (MOF) with dodecahedron shape by the decomposition of Co-based precursor of zeolitic imidazolate framework (ZIF -67). And to further improve the absorbing performance, acetylene was introduced to obtain ultra-small Co/CNTs nanohybrids. During CVD process, Co nanoparticles of MOF cracked into Co nanocrystals catalyzing the growth of carbon nanotubes (CNTs). Among three composites of ZIF-67, MOF and Co/CNTs, the Co/CNTs presented the better performance for electromagnetic wave absorption. Particularly, the maximum reflection loss (RL) of Co/CNTs reached −49.16 dB in case of the absorber thickness of 2.5 mm. The excellent absorbing performance is more likely attributed to the novel structure and the double losses of magnetic Co and dielectric CNTs.

Taking into account the high demands and applications of amorphous SiO2 in various nanostructured forms, here we have synthesized various nanostructures of SiO2 including nanosprings, straight nanofibers, nanotubes and nanobelts. A simple catalytic chemical vapor deposition (CCVD) technique is developed where Si, SiO2 and graphene capsules are utilized as starting materials. The structural and chemical analysis of the as-prepared nanostructures confirms the amorphous nature of SiO2 and shows the minor existence of SiC, which acts as a growth directing agent for various shapes of SiO2. The electron microscopic observations delineate the morphologies of the as-prepared nanostructures with different shapes i.e. nano-fibers, tubes, springs and belts. It is observed that straight SiO2 fibers having diameter of ∼440 nm are thicker than the fibers (∼220 nm) constructing the nanosprings while the overall helical diameter falls in the range of 530–690 nm. The in-depth structural and morphological studies reveal that the growth mechanism of SiO2 nanostructures is in the vapor-liquid-solid (VLS) growth mode. The unique microstructures with special morphologies straight, helical and hollow shapes make them potential candidate for several functional applications such as nanoelectron-magnetic devices, mechanical sensor system and flexible energy storage devices.

Rare-earth metal (Eu) doped aluminum nitride has potential application as luminescence materials due to its unusual mechanical and physical properties, as well as high chemical stability. Here we investigate the energetics, local structure and optical and electronic properties by means of a combination of experimental observations (XDR, SEM, HR-TEM and XANES) and first-principles simulations. Present study has revealed that Eu ions are likely to be co-doped with O in the form of Eu-O pairs. Eu ions or Eu-O pairs favor participation at the surfaces of the AlN crystallites. Our analyses show dependences of the Eu valence and electronic/optical properties on the local chemical composition and structure. The obtained information helps us to realize tuning of the optical properties of the luminescent materials via composition and site occupation modification. National Natural Science Foundation of China. Grant Number: 51302029; Fundamental Research Funds for the Central Universities. Grant Number: ZYGX2015J110.

Performing carbon coating on the surface of phosphors has been proven to be an effective strategy to enhance the oxidation resistance, which is an important factor to achieve stable luminescent devices. Therefore, a good understanding of the protection mechanism favors a continuous improvement of oxidation resistance of phosphors. In present paper, the evolution of the carbon layer, Eu valence (Eu 2+ /Eu 3+ ), and luminescent properties for the C coated BaMgAl 10 O 17 : Eu 2+ phosphor when annealed at high temperature is investigated carefully. Decrease of carbon layer promotes the appearance color transition from black to white as the annealing temperature rises to 1000 °C in air. As expected, the decrease of carbon layer will enhance the luminescence intensity, but risk the possible oxidation of Eu 2+ to Eu 3+ , which inhibits the blue emission ascribed to Eu 2+ . The results indicate that luminescence intensity of phosphor is dependent on the synergistic effect of carbon thickness and Eu 2+ /Eu 3+ ratio. Additionally, a reduction reaction of Eu 3+ to Eu 2+ is observed in C coated BaMgAl 10 O 17 : Eu 2+ phosphor when annealed at high temperature, which also contributes to the higher luminescence intensity.

Microwave absorption is a critical challenge with progression in electronics, where fine structural designing of absorbent materials plays an effective role in optimizing their microwave absorption properties. Here, we have developed Fe3O4@C (FC) and Fe-Fe3O4@C (FFC) hybrid nanorings via a hydrothermal method coupled with a chemical catalytic vapor deposition technique. FC and FFC hybrid nanorings have fine carbon coating while their size can easily be tunable in a certain range from 80-130 to 90-140 nm. The optimized FC and FFC hybrid nanorings bear minimum reflection loss (RL) values of -39.1 dB at 15.9 GHz and -32.9 dB at 17.1 GHz, respectively, whereas FFC shows an effective absorption bandwidth (RL values < -10 dB) ranged from 5.2 to 18 GHz. Such an enhanced microwave absorption performance of hybrid nanorings is mainly due to the suitable impedance characteristics, multilevel interfaces, and polarization features in nanorings. This work provides an approach to design hybrid materials having a complex structure to enhance the microwave absorption properties.

A facile approach to fabricate nanoholes on the surface of a phosphor via a carbothermal reaction between C and BaMgAl10O17 was adopted. Drilling nanoholes greatly enhanced excitation light absorption and consequently increased the quantum efficiency, which provided new insight to help improve the luminescence efficiency of oxygen-containing phosphors.

The inevitable corrosion of magnetic microwave absorber (MA) remains a great challenge to adapt oxygen-containing environment. Herein we developed a plasma-induced approach for protecting the magnetic MA by anchoring robust SiO2 layers on their surface. Keeping the original flaky shape of FeSiAl (FSA) led to breaking the Snoek limit, which brought excellent ultra-low-frequency absorption. In detail, the ultrathin amorphous silica layer (5 nm) grew on FSA surface by the facile Stober method at low cost firstly. Plasma technology was introduced to make these SiO2 layers dense and attain the integrated P-FSA@SiO2. SiO2 layer protected FSA from the corrosive medium, which increased polarization resistance to 186.9 kΩ·cm2 of P-FSA@SiO2 (from 97.46 kΩ·cm2 of pure FSA) and decreased the corrosion current to 18.45 μA/cm2 (from 63.35 μA/cm2). The corrosion of the samples in acid solution also verified the electrochemical characterizations. Meanwhile, rich interface and sheet ordered structure enable P-FSA@SiO2 exhibit enhanced microwave absorption in ultra-low-frequency through multiple reflections, magnetic loss and the interface polarization between core and shell. The minimum reflection loss of P-FSA@SiO2 reduced from −8.0 dB (FSA) to −12.4 dB and the efficient absorption band (

Corrosive ions with immense penetrating ability often invalidate the traditional microwave absorber as well as cause severe corrosion. Herein, an inorganic/organic bilayer structure of silicon dioxide/polyurethane-acrylic (SiO2@PUA) is developed layer by layer on FeSiAl surface for addressing the dual-function of microwave absorption and anti-corrosion properties. The bilayer structure possesses the inorganic SiO2 layer with physical barrier function and organic outer layer (PUA) of hydrophobic nature. The as-prepared FeSiAl@SiO2@PUA composite structure filled with 20 wt% of paraffin wax displays a maximum reflection loss of −49 dB at 5.8 GHz, and a broad effective absorption bandwidth reaches 7.8 GHz (10.2–18 GHz) at 2.5 mm thickness. Besides, the corrosion behavior of FeSiAl, FeSiAl@SiO2, and FeSiAl@SiO2@PUA is investigated by immersing in a corrosive environment and electrochemical testing. Due to the multi-level protection of SiO2/PUA bilayer, the FeSiAl@SiO2@PUA is immersed in an alkaline salty environment (pH = 12) for 3930 h and the corresponding corrosion potential significantly increases from −0.166 to −0.047 V, indicating the enhanced anti-corrosion with relatively low corrosion current 2.16 × 10-6 A/cm2 and corrosion rate (6.94 × 10-13 m/s). The designing inorganic/organic hybrid structure provides an effective strategy to enhance the dual-function of microwave absorption and anti-corrosion and its application at the commercial level.