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In this study, we successfully developed two novel vinylene‐linked covalent organic frameworks (COFs) using 2‐connected 3,6‐dimethylpyridazine through Knoevenagel condensation. These COFs featured finely tailored micro‐/nano‐scale pore sizes, high surface areas and stable non‐polar vinylene linkages. Finely resolved powder X‐ray diffraction patterns demonstrated highly crystalline structures with a hexagonal lattice in the AA layer stacking. The resulting one‐dimensional channels possess strong hydrogen‐bond accepting sites arising from the decorated cis‐azo/azine units with two pairs of fully exposed lone pair electrons, endowing the as‐prepared COFs with exceptional water absorption properties. The g‐DZPH‐COF exhibited successive steep water uptake steps starting from low relative pressures (P/PSTA=0.1), with the remarkable water uptake capacity of 0.26 g/g at P/PSTA=0.2 (25 °C), which is the optimal value recorded among the reported COFs. Dynamic vapour sorption measurements revealed the fast kinetics of these COFs, even in the cluster formation process. Water uptake and release cycling tests demonstrated their outstanding hydrolytic stability, durability, and adsorption–desorption retention ability. [ABSTRACT FROM AUTHOR]

In this study, we successfully developed two novel vinylene‐linked covalent organic frameworks (COFs) using 2‐connected 3,6‐dimethylpyridazine through Knoevenagel condensation. These COFs featured finely tailored micro‐/nano‐scale pore sizes, high surface areas and stable non‐polar vinylene linkages. Finely resolved powder X‐ray diffraction patterns demonstrated highly crystalline structures with a hexagonal lattice in the AA layer stacking. The resulting one‐dimensional channels possess strong hydrogen‐bond accepting sites arising from the decorated cis‐azo/azine units with two pairs of fully exposed lone pair electrons, endowing the as‐prepared COFs with exceptional water absorption properties. The g‐DZPH‐COF exhibited successive steep water uptake steps starting from low relative pressures (P/PSTA=0.1), with the remarkable water uptake capacity of 0.26 g/g at P/PSTA=0.2 (25 °C), which is the optimal value recorded among the reported COFs. Dynamic vapour sorption measurements revealed the fast kinetics of these COFs, even in the cluster formation process. Water uptake and release cycling tests demonstrated their outstanding hydrolytic stability, durability, and adsorption–desorption retention ability. [ABSTRACT FROM AUTHOR]

The high price and safety concerns have driven people to turn to research aqueous batteries. Among them, aqueous metal-ion batteries, metal-air batteries and metal-hydrogen peroxide batteries stand out because of their high energy density, power density and long duration. In particular, metal hydrogen peroxide batteries have become popular due to their oxygen independence, which results in great performance while working in situations without oxygen, such as space or water. Here, we provide the requirements of underwater batteries and review their progress. Then, we discuss the advantages and disadvantages of different batteries and show some applications of underwater power batteries. Finally, we provide an outlook on underwater power batteries and some important issues for future progress. [ABSTRACT FROM AUTHOR]

The aim of this study is to investigate the impact of the Kovar glass content on the mechanical and electrical properties of Si3N4–Kovar composites sintering at air atmosphere. To achieve this, Si3N4–Kovar composites were prepared using molding technology with the Kovar glass powder ranging from 20 to 70 wt%. The phase composition, morphology, bulk density, apparent porosity, flexural strength at room temperature, dielectric constant, and dielectric loss of the composites were all examined in relation to changing the Kovar glass content. During the sintering process, the α‐quartz on the surface of Si3N4 particles acted as the crystal nucleus, inducing the crystallization of the glass at the wetting position that the Kovar glass and the surface of the Si3N4 particles. A small amount of the β‐quartz phase was crystallized at 750–850°C, followed by a large amount of the β‐quartz phase crystallizing above 900°C. Additionally, some β‐quartz phase transformed into the metastable β‐cristobalite phase that could exist below 1470°C. During the cooling process, the β‐cristobalite phase transformed into a low‐temperature α‐cristobalite phase, while the β‐quartz phase transformed into a low‐temperature α‐quartz phase. The results indicate that the Si3N4–Kovar glass composite with 60 wt% the Kovar glass content sintered at 900°C exhibits higher density (1.88 g/cm3), lower porosity (25.4%), higher flexural strength (55.34 MPa), lower dielectric constant (3.46), and lower dielectric loss (4.26 × 10−3). [ABSTRACT FROM AUTHOR]

The leaching solution from the direct reduction-sodium smelting process of ultra-poor vanadium-bearing titanomagnetite contained sodium, vanadium, and impurities. It was carbonated to ensure sodium recovery, and the recovery of vanadium proved challenging. This study proposed and optimized a novel process of extracting vanadium from this alkaline carbonated solution using the transformed organic phase of 20 vol% (0.44 mol/L) Aliquat 336, 8 vol% 2-octanol, and 72 vol% sulfonated kerosene. To achieve superior vanadium extraction, Aliquat 336 in the organic phase was transformed into carbonate type by successively washing with NaHCO3 and NaOH solutions. The single-stage extraction efficiency of vanadium exceeded 85% at a pH of 8.0‒9.0 and an organic-to-aqueous phase ratio of 1:1. The thermodynamics of the vanadium extraction process was examined, confirming that the extraction process is an exothermic reaction (ΔH0 = −9.56 kJ/mol). Furthermore, using a solution of 4 mol/L NH4Cl and 1 mol/L NH4OH with a pH of 8.8 as the effective stripping reagent to realize one-step stripping and precipitation of vanadium, the single-stage stripping efficiency of vanadium was 99.8%, and the precipitation efficiency was about 95%. Through this stripping-precipitation process, solid ammonium metavanadate with a purity of 98.14% was obtained in one step. The mechanisms of transformation, extraction, and stripping were studied via infrared spectra of the organic phases. [ABSTRACT FROM AUTHOR]

Low back pain (LBP) is a leading cause of global disabilities. Numerous molecular, cellular, and anatomical factors are implicated in LBP. Current issues regarding neurologic alterations in LBP have focused on the reorganization of peripheral nerve and spinal cord, but neural mechanisms of exactly what LBP impacts on the brain required further researches. Based on existing clinical studies that chronic pain problems were accompanying alterations in brain structures and functions, researchers proposed logical conjectures that similar alterations occur in LBP patients as well. With recent extensive studies carried out using noninvasive neuroimaging technique, increasing number of abnormalities and alterations has been identified. Here, we reviewed brain alterations including white matters, grey matters, and neural circuits between brain areas, which are involved in chronic LBP. Moreover, brain structural and functional connectivity abnormalities are correlated to the happening and transition of LBP. The negative emotions related to back pain indicate possible alterations in emotional brain regions. Thus, the aim of this review is to summarize current findings on the alterations corresponding to LBP in the brain. It will not only further our understanding of etiology of LBP and understanding of negative emotions accompanying with back pain but also provide ideas and basis for new accesses to the diagnosis, treatment, and rehabilitation afterward based on integral medicine. [ABSTRACT FROM AUTHOR]

Latex films with high heat resistance tend to have higher Tg and the emulsion minimum film formation temperature (MFFT) is higher. Higher MFFT latexes do not produce continuous coherent films at low temperatures during application. Consequently, in order to solve the paradoxical problem of obtaining latex films with high Tg at low emulsion MFFT, a series of alkali soluble resin (ASR) stabilized latexes were synthesized in this study using a semi‐continuous pre‐emulsification polymerization process. The microstructure of latex particles, polymerization stability, composition and properties of latex films were characterized and tested by ATR‐FTIR, TEM, ZETA potential analyzer, DSC, orthomorphic metallographic microscope, and gloss tester. The results show that the addition of ASR reduces the content of coagulum during polymerization and significantly increases the number of latex particles. The high Tg ASR also induces the formation of a microphase separation structure with a dual glass transition in the latex film, which improves heat resistance. Additionally, hydroplasticized ASR reduces emulsion MFFT, improves latex film flatness, and enhances its glossiness. The introduction of ASR acts as a dual role of synergy with conventional ionic surfactants during synthesis to increase the stability of composite latexes and with polyacrylate (PA) in application to enhance its properties. [ABSTRACT FROM AUTHOR]

Vinylene‐linked covalent organic frameworks (COFs) are emerging as promising crystalline materials, but their narrow pore engineering is severely impeded by the weak reversibility of the carbon‐carbon double bond formation reaction, which has led to less exploration of their ultramicroporous structures and properties. Herein, we developed a single aromatic ring‐based tetratopic monomer, tetramethylpyrazine, which undergoes a smooth Knoevenegal condensation at its four arylmethly carbon atoms with linear aromatic dialdehyde monomers upon the self‐catalyzed activation of pyridine nitrogen‐containing monomers in the presence of an organic anhydride. This has resulted in the formation of two vinylene‐linked COFs, which both crystallized in orthorhombic lattices, and layered in AA stacking fashions along the vertical directions. They exhibit high surface areas and well‐tailored ultramicropore sizes up to 0.5 nm. The unique cross‐linking mode at two pairs of para‐positions of each pyrazine unit through carbon‐carbon double bonds afford them with π‐extended conjugation over the in‐plane backbones and substantial semiconducting characters. The resultant COFs can be well‐dispersed in water to form stable sub‐microparticles with negative charges (zeta potentials: ca. −30 mV), and exhibiting tunable aggregation behaviors through protonation/deprotonation. As a consequence, they exhibit pore‐size‐dependent colorimetric responses to various anions with different pKa values in high selectivity. [ABSTRACT FROM AUTHOR]

Vinylene‐linked covalent organic frameworks (COFs) are emerging as promising crystalline materials, but their narrow pore engineering is severely impeded by the weak reversibility of the carbon‐carbon double bond formation reaction, which has led to less exploration of their ultramicroporous structures and properties. Herein, we developed a single aromatic ring‐based tetratopic monomer, tetramethylpyrazine, which undergoes a smooth Knoevenegal condensation at its four arylmethly carbon atoms with linear aromatic dialdehyde monomers upon the self‐catalyzed activation of pyridine nitrogen‐containing monomers in the presence of an organic anhydride. This has resulted in the formation of two vinylene‐linked COFs, which both crystallized in orthorhombic lattices, and layered in AA stacking fashions along the vertical directions. They exhibit high surface areas and well‐tailored ultramicropore sizes up to 0.5 nm. The unique cross‐linking mode at two pairs of para‐positions of each pyrazine unit through carbon‐carbon double bonds afford them with π‐extended conjugation over the in‐plane backbones and substantial semiconducting characters. The resultant COFs can be well‐dispersed in water to form stable sub‐microparticles with negative charges (zeta potentials: ca. −30 mV), and exhibiting tunable aggregation behaviors through protonation/deprotonation. As a consequence, they exhibit pore‐size‐dependent colorimetric responses to various anions with different pKa values in high selectivity. [ABSTRACT FROM AUTHOR]

Carbon fibers (CFs) have been innovated in the application of fiber‐shaped and wearable energy storage devices recently. However, time‐ and energy‐consuming activation process under harsh conditions is generally required to modify the surface structure of the CF. Herein, a fast and effective Joule heating activation method is proposed with the nickel–cobalt layered double hydroxide‐derived nanometal particles as the template. The resultant Joule heating‐activated CF (JACF) demonstrates excellent capacitive performance with an electrode capacitance of 268 F g−1. After assembling into a solid‐state fiber‐shaped supercapacitor (FSC), the device shows both enhanced specific capacitance and energy/power densities, as well as the long cycling stability of over 5000 cycles. The Joule heating method reported in this work is time and energy saving for CF activation compared with the traditional chemical etching or high‐temperature annealing processes, and it is promising for the large‐scale production of high‐performance fiber‐shaped and wearable energy devices. [ABSTRACT FROM AUTHOR]

Conjugated porous polymers are emerging as sustainable and reliable electrode materials for lithium-ion batteries, owing to their versatile chemical modification, environmental-friendliness, and low cost, but still suffer from insufficient redox-active sites and sluggish ion/electron transport. Here, two new kinds of porous polymers (denoted as TPT-CMP and BFT-CMP), comprising full sp2-carbon skeletons connected through vinylidene linkages, are synthesized by acid-catalyzed Knoevenagel condensation of ethene-1,1,2,2-tetrayl-tetrakis-1,1′-biphenyl-4-carbaldehyde and 9,9′-bifluorenylidene-3,3′,6,6′-tetrayl-tetrabenzaldehyde with s-indacene-1,3,5,7-(2H,6H)-tetraone, respectively. Such porous polymers were readily composited with carbon nanotubes to form freestanding thin films upon a simple vacuum-assisted filtration. As the anode, the TPT-CMP-based film delivered a much higher capacity of 550 mA h g−1 at 100 mA g−1 than the BFT-CMP-based one (407 mA h g−1), although TPT-CMP exhibits a much lower surface area of 535.92 m2 g−1 than that (934.41 m2 g−1) of BFT-CMP. This phenomenon might be attributed to the idea that the conformationally rotatable tetraphenylethylene moieties in the case of TPT-CMP might improve rapid mass transport. Both composite electrodes can sustain 500 cycles without any significant decay. These results set new capacity records among porous polymer-based lithium-ion batteries and suggest a new method for achieving promising anode materials by rationally designing the main backbones of conjugated porous polymers. [ABSTRACT FROM AUTHOR]

BaTi4O9–Ba2Ti9O20 composite phase ceramics with high Q × f as well as near-zero τf were obtained using a conventional solid-phase reaction method. The effect of WO3/CeO2 co-doping on the microwave dielectric properties of the samples was analyzed. The effect of CeO2 doping on the microwave dielectric properties of composite ceramics was investigated. The relationship between WO3 doping and phase evolution, grain morphology distribution and microwave dielectric properties were investigated. The εr, Q × f and τf values were closely correlated to phase composition, such as BaTi4O9, Ba2Ti9O20, BaWO4. When sintered at 1325 °C, the ceramics co-doped 0.07WO3/0.5wt%CeO2 have excellent dielectric properties: εr = 37.81, Q × f = 51,531 GHz, τf = + 3.33 ppm/°C. It may be a candidate material for 5G ceramic filter applications. [ABSTRACT FROM AUTHOR]

A porous carbon structure (PCS) is considered as an ideal electrode material for lithium–sulfur (Li–S) batteries, owing to its flexible texture, large surface area, and high electrical conductivity. In this work, we use food-grade yeast as the carbon precursor, which is proliferated in glucose solution, carbonized with a NaCl template to yield a sheet-like carbon structure, and reactivated at different temperatures with KOH. The porous carbon material is then applied as the sulfur host of the Li–S battery cathode, and the electrode is systematically characterized by means of SEM, TEM, XRD, Raman, XPS, thermogravimetric (TG), nitrogen gas adsorption–desorption, and electrochemical measurements. The results show that the PCS obtained at 800 °C has an ultra-high surface area of 2410 m2 g−1 and exhibits excellent performance for a Li–S battery cathode. The initial discharge capacity of the PCS-800/S cathode is 1502 mAh g−1, which accounts for 90% of the theoretical capacity value. [ABSTRACT FROM AUTHOR]

Antibodies targeting the programmed cell death protein 1/programmed cell death ligand-1 (PD-1/PD-L1) pathway have dramatically changed the treatment landscape of advanced non-small cell lung cancer (NSCLC). However, combination approaches are required to extend this benefit beyond a subset of patients. In addition, it is of equal interest whether these combination therapy can be applied to neoadjuvant therapy of early-stage NSCLC. In this study, we hypothesized that combining immunotherapy with anti-angiogenic therapy may have a synergistic effect in local tumor control and neoadjuvant therapy. To this end, the effect of combination of bevacizumab and pembrolizumab in humanized mouse models was evaluated. Furthermore, we innovatively constructed a neoadjuvant mouse model that can simulate postoperative recurrence and metastasis of NSCLC to perform neoadjuvant study. Tumor growth and changes in the tumor vasculature, along with the frequency and phenotype of tumor-infiltrating lymphocytes, were examined. Additionally, in vivo imaging system (IVIS) was used to observe the effect of neoadjuvant therapy. Results showed that combination therapy could inhibited tumor growth by transforming tumor with low immunoreactivity into inflamed ('hot') tumor, as demonstrated by increased CD8+granzyme B+ cytotoxic T cell infiltration. Subsequent studies revealed that this process is mediated by vascular normalization and endothelial cell activation. IVIS results showed that neoadjuvant therapy can effectively prevent postoperative recurrence and metastasis. Taken together, these preclinical studies demonstrated that the combination of bevacizumab and pembrolizumab had a synergistic effect in both advanced tumor therapy and neoadjuvant setting and therefore provide a theoretical basis for translating this basic research into clinical applications. [ABSTRACT FROM AUTHOR]

Hierarchically macro–meso–microporous ZIF-67/nori-derived electrocatalysts were synthesized by using single-cell-array nori and ZIF-67 as macroporous and microporous templates, and KOH as a meso/micropore-forming reagent. The ZIF-67/nori-800-based Zn–H2O2 battery achieved a high maximum power density, of 476 mW cm−2, and a specific energy density of 964 W h kg−1 at 50 mA cm−2. [ABSTRACT FROM AUTHOR]

The efficient 810 nm laser energy conversion of glass frit had been proven to be the key to the long‐term hermetic encapsulation of Organic Light Emitting Display (OLED). A direct laser energy conversion laser‐assisted Bi2O3‐B2O3‐ZnO‐Nd2O3 sealing glass material without extra laser absorbent such as carbon black, was designed and systematically investigated. The addition of Nd2O3, as glass modifiers with higher cationic field strength, could be conducive to enhancing the polymerization of glass network structure, manifesting that the glass‐transition temperature Tg, onset‐crystallization temperature Tc and thermal stability ΔT (ΔT = Tc‐Tg) increased, while thermal expansion coefficient CTE dropped to 9.72×10−6/°C and advantageously matched with the glass substrate (8±1×10−6/°C). More importantly, the absorption rate of BBZ‐Nd glass was more than 50 % between 800∼810 nm owing to the 4f‐4f electron transition of Nd3+ ions, and yet the reflectivity and transmittance of the wavelength at 800–810 nm were lower. As optimal compositions, the addition of 3.0 wt% Nd2O3 in Bi2O3‐B2O3‐ZnO‐Nd2O3 glass frit with higher absorption coefficients (80 %) led to instantaneous bonding encapsulation between glass substrates without interfacial cracks or pores with the 808 nm wavelength of the laser at 20 W and 2.4 mm/s. [ABSTRACT FROM AUTHOR]

The 0.9Mg2SiO4-0.1CaTiO3 (MSCT) ceramics with 60ZnO-20B2O3-20SiO2 glass (ZBS) and LiF compound additives were prepared by solid-state reaction method. The effects of different ZBS contents on the phase, densification temperature, surface morphology and dielectric properties of MSCT ceramics were studied. The results show that ZBS can inhibit the reaction between LiF and CaTiO3, which improve the surface morphology and reduce the sintering temperature of MSCT ceramics. The sample of MSCT with 2wt%ZBS-1.5wt%LiF sintered at 900 °C for 90 min shows excellent microwave dielectric properties: εr = 9.26, Q × f = 68,580 GHz (at 15.5 GHz) and τf = -1.49 ppm/ °C. There is no obvious element diffusion at the co-firing interface between dielectrics and Ag electrodes, indicating it is a promising candidate for LTCC applications. [ABSTRACT FROM AUTHOR]

A facile double flexible interfacial imprinting method is reported to obtain the cubic single‐crystal CH3NH3PbBr3 sheets with in situ polymer patterns by capillary effect. The imprinted CH3NH3PbBr3 sheets offer good crystallinity and light‐trapping structure. As a result, the textured single‐crystal photodetector exhibits the superior responsivity of 63.0 A W−1, external quantum efficiency of 1.50 × 104%, and detectivity D* of 8.12 × 1012 Jones under 520 nm irradiations with a weak power density of 0.54 µW cm−2 at 3 V, which are more than 4200% and 80000% higher than those of the photodetector based on single‐crystal bulk and polycrystalline film, respectively. The exciting ultraweak‐light photoelectric performance is achieved due to the good light trapping and high carrier collection. Especially, the photodetector also exhibits excellent self‐powered performance. [ABSTRACT FROM AUTHOR]

V-bearing molten iron was obtained by adding Na2CO3 in the smelting process of vanadium titanomagnetite at low temperature. Two forms of V-rich carbides ((Fe,V)3C, VC) were detected in the V-bearing pig iron products. Once the smelting temperature was above 1300 °C, most of the V in the raw ore was reduced into molten iron. Owning to the high content of V, the unsteady (Fe,V)3C solid solution decomposed along with the precipitation of graphite and VC during the solidification process. The presence of VC cluster and VC precursor in (Fe,V)3C was detected by transmission electron microscopy, which confirmed the possibility of this transition process at the atomic perspective. The transformation dramatically affected the compositions and properties of V-bearing pig iron and had important guiding significance for the actual production process. [ABSTRACT FROM AUTHOR]

BaTi1-x(Sb0.5Nb0.5)xO3 ceramics (0.01 ≤ x ≤ 0.3) were prepared by solid-state reaction method. The effect of co-substituting Ti4+ with Sb3+ and Nb5+ on its crystal structure, microstructure, and dielectric properties was studied. When 0.01 ≤ x ≤ 0.1, a single-phase barium titanate solid solution can be obtained; when 0.15 ≤ x ≤ 0.25, a small amount of unknown second phase was appeared; and when the composition (x) increases to 0.3, a large amount of unknown second phases are precipitated. The main crystal phase of BaTi1-x(Sb0.5Nb0.5)xO3 ceramics has a change of tetragonal to cubic with the increase of x. As x increases from 0.1 to 0.25, the dielectric constant decreases from 1264 to 214, the dielectric loss decreases from 0.253% to 0.046% (1 MHz, 25 °C), the capacitance temperature coefficient changes from − 7897 to − 1657 ppm/ °C, and the insulation resistivity is greater than 1012 Ω cm. This means that BaTi1-x(Sb0.5Nb0.5)xO3 (x = 0.1 ~ 0.25) ceramics can be suitable for temperature-compensated ceramic capacitors. [ABSTRACT FROM AUTHOR]

The flake alumina filler is added to improve the bending strength in BaZrO3 (BZ)/BaO-MgO-ZnO-SiO2-B2O3 (BBSMZ) glass for the application of low temperature co-fired ceramics. The effects of flake alumina filler for BaZrO3/BaO-MgO-ZnO-SiO2-B2O3 on phase, microstructure, dielectric and mechanical property are studied. With the increase of flake Al2O3 content, flake Al2O3 phase appears, BaZrO3, BaZr(BO3)2, BaZn2Si2O7 phase decreases, dielectric constant decreases and dielectric loss increases. By adding flake Al2O3, the mechanical strength of the material increases. Under the same sintering conditions, the bending strength (205 MPa) of the laminated sample increased by nearly 60% compared with the same content flake alumina block sample (124 MPa), and increased by 162% compared with the sample without flake alumina (78 MPa). BZ-BBSMZ-5 wt% flake Al2O3 ceramic sintered satisfactorily at 940 °C with tanδ = 4.82*10–4 (10 GHz), εr = 11.66. The bending strength of the sample is 205 Mpa. [ABSTRACT FROM AUTHOR]

Acute kidney injury (AKI) is described as the abrupt decrease in kidney function always accompanied by inflammation. The roots of Oxybaphus himalaicus Edgew. have long been used in Tibetan folk medicine for the treatment of nephritis. Nevertheless, modern pharmacological studies, especially about the underlying mechanism of O. himalaicus medications, are still lacking. Here, in lipopolysaccharide (LPS)-induced RAW264.7 macrophages, the O. himalaicus extract (OE) showed significant anti-inflammatory activity with the dose dependently reducing the LPS-stimulated release of nitric oxide and the mRNA level and protein expression of inflammatory cytokines and reversed the activation of nuclear factor kappa B (NF-κB). Co-immunoprecipitation assay indicated that OE inhibited Toll-like receptor 4/myeloid differentiation factor 2 (TLR4/MD2) complex formation and further suppressed both myeloid differentiation factor 88 (MyD88)-dependent and TIR-domain-containing adapter-inducing interferon-β (TRIF)-dependent cascades activation. In addition, OE could restrain NADPH oxidase 2 (NOX2) endocytosis by blocking TLR4/MD2 complex formation to prevent reactive oxygen species production. In LPS-induced AKI mice, OE treatment mitigated renal injury and inflammatory infiltration by inhibiting TLR4/MD2 complex formation. UPLC-MS/MS analysis tentatively identified 41 components in OE. Our results indicated that OE presented significant anti-inflammatory activity by inhibiting TLR4/MD2 complex formation, which alleviated LPS-induced AKI in mice. [ABSTRACT FROM AUTHOR]

In this work, Al2O3–CeMgAl11O19 composites were sintered at 1530 °C for 3 h with the wet nitrogen–hydrogen atmosphere in the tunnel kiln for HTCC application. The effects of the CeMgAl11O19 content on the mechanical and dielectric properties were investigated. The results indicated that the CeMgAl11O19 platelets significantly enhanced the mechanical property and slightly reduced the grain size of Al2O3. The optimum bending strength was 450 MPa with 8 wt% CeMgAl11O19 addition. But further additions would promote the abnormal growth of grains and increase porosity. CeMgAl11O19 exhibited insignificant effects on the dielectric properties of composite ceramics, with all samples having dielectric constants in the range of 9–10 and acceptable dielectric losses. For the composite ceramics with 8 wt% CeMgAl11O19, a strong metal–ceramic combination was obtained with metallization adhesion strength greater than 44.5 N/mm2. [ABSTRACT FROM AUTHOR]

Fabricating flexible, solid, miniature and low-cost energy storage units has received growing attention as the rapid development of flexible electronic devices. Herein, we demonstrate the easy manufacturing of all-solid-state flexible supercapacitor with in-plane interdigital electrode architecture based on nickel–cobalt bimetallic sulfide NiCo2S4. With the help of a shadow mask printing technique, the NiCo2S4-based electrodes were printed on a flexible PET substrate using the home-made ink comprised of NiCo2S4, carbon nanotubes, PTFE and terpineol. Then a PVA-KOH gel electrolyte was coated and cured to complete the assembly of interdigital supercapacitor. The NiCo2S4 electrode exhibits a high specific capacitance of 1401 F/g. After 3000 cycles, the capacitance retention maintains 90%, showing a remarkable cycle stability. The assembled interdigital device delivers a high specific areal capacitance of 13.6 mF/cm2 at a current density of 0.35 mA/cm2 and an excellent energy density of 2.1 μWh/cm2 at a power density of 0.189 mW/cm2, with both long-term cycling and high rate stability. The electrochemical performance remained consistent at different bending angles (0°, 90° and 180°). This work demonstrates a simple and low-cost preparation of printable supercapacitor based on NiCo2S4 interdigital electrodes, which has a great potential to be used for flexibility, wearable and portable devices. [ABSTRACT FROM AUTHOR]

The poor operational stability of electrolytes is a persistent impediment in building redox flow battery technology; choosing suitable stability additives is usually the research direction to solve this problem. The effects of five phosphate containing additives (including 1-hydroxyethylidene-1,1-diphosphonic acid (HEDP), hexamethylene diamine tetramethylene phosphonic acid (HDTMPA), amino trimethylene phosphonic acid (ATMPA), sodium ethylenediamine tetramethylene phosphonate (EDTMPS), and diethyl triamine pentamethylene phosphonic acid (DTPMP)) on the thermal stability and electrochemical performance of the positive electrolyte of vanadium redox flow battery were investigated. With 0.5 wt% addition, most of the selected additives were able to improve the thermal stability of the electrolyte. HEDP and HDTMPA extended the stability time of the pentavalent vanadium electrolyte at 50 °C from 5 days (blank sample) to 30 days and 15 days, respectively. The electrochemical performance of the electrolyte was further investigated by cyclic voltammetry, steady state polarization, and electrochemical impedance spectroscopy tests. It was found that most of the additives enhanced the electrochemical activity of the positive electrolyte, and the diffusion coefficients, exchange current densities, and reaction rate constants of V(IV) species became larger with the addition of these additives. It is verified that the thermal stability and electrochemical stability of the electrolyte are significantly improved by the combination of ATMPA + HEDP or ATMPA + HDTMPA. This study provides a new approach to improve the stability of the positive electrolyte for vanadium redox flow battery. [ABSTRACT FROM AUTHOR]

Knoevenagel condensation is a powerful tool for the construction of vinylene‐linked covalent organic frameworks. Herein, we established a concise approach to vinylene‐linked COFs by Knoevenagel condensation at the multi‐methyl groups of a pyridine ring through in situ formation of an N‐acyl pyridinium cation in the presence of various acylating reagents. Following this strategy, two vinylene‐linked COFs were constructed using 2,4,6‐trimethylpyridine and multi‐aldehyde‐substituted aromatic derivatives as monomers. The resultant COFs are highly crystalline and assembled into hexagonal lattices with specific surface areas as large as 1915 m2 g−1 (vs. 1972 m2 g−1 of the theoretical value). The stable and abundant pyridine‐decorated regular nanochannels within the COFs allow for catalyzing the esterification of several pharmaceutical intermediates with distinct spatially confined selectivity and recyclability, representing an environmentally friendly catalytic organic transformation. [ABSTRACT FROM AUTHOR]

Knoevenagel condensation is a powerful tool for the construction of vinylene‐linked covalent organic frameworks. Herein, we established a concise approach to vinylene‐linked COFs by Knoevenagel condensation at the multi‐methyl groups of a pyridine ring through in situ formation of an N‐acyl pyridinium cation in the presence of various acylating reagents. Following this strategy, two vinylene‐linked COFs were constructed using 2,4,6‐trimethylpyridine and multi‐aldehyde‐substituted aromatic derivatives as monomers. The resultant COFs are highly crystalline and assembled into hexagonal lattices with specific surface areas as large as 1915 m2 g−1 (vs. 1972 m2 g−1 of the theoretical value). The stable and abundant pyridine‐decorated regular nanochannels within the COFs allow for catalyzing the esterification of several pharmaceutical intermediates with distinct spatially confined selectivity and recyclability, representing an environmentally friendly catalytic organic transformation. [ABSTRACT FROM AUTHOR]

In this paper, a flexible skin inspired by the sudoriferous gland structure of human skin is developed for ultra-thermal protection of hypersonic morphing vehicles. The effect of different coolants and cooling flow rates on the cooling performance of the leading edge is studied using finite element analysis. A wind tunnel experiment is conducted at high temperatures with the heat flux Q = 700 kW/m2, and the results indicate the following: (1) the flexible skin can effectively reduce the surface temperature of hypersonic vehicles; (2) when using liquid water instead of argon as the cooling medium, the cooling efficiency of flexible skin performs better; (3) when liquid water is used as the cooling medium, the cooling effect peaks at a flow rate of 0.01 m/s, and further increasing the flow rate will not benefit cooling efficiency significantly; (4) the flexible skin can withstand extreme thermal environments, demonstrating its feasibility in applications of over-limit thermal protection for hypersonic morphing vehicles. This study aims at optimizing the cooling performance of the flexible skin for ultra-thermal protection. The proposed skin can overcome the heat-resistance limit of flexible materials with morphing properties, laying a theoretical and experimental foundation for its future applications in hypersonic morphing vehicles. [ABSTRACT FROM AUTHOR]

Background: Circulating tumor DNA (ctDNA) has been proven as a marker for detecting minimal residual diseases following systemic therapies in mid-to-late-stage non-small-cell lung cancers (NSCLCs) by multiple studies. However, fewer studies cast light on ctDNA-based MRD monitoring in early-to-mid-stage NSCLCs that received surgical resection as the standard of care. Methods: We prospectively recruited 128 patients with stage I–III NSCLCs who received curative surgical resections in our Lung Cancer Tempo-spatial Heterogeneity prospective cohort. Plasma samples were collected before the surgery, 7 days after the surgery, and every 3 months thereafter. Targeted sequencing was performed on a total of 628 plasma samples and 645 matched tumor samples using a panel covering 425 cancer-associated genes. Tissue clonal phylogeny of each patient was reconstructed and used to guide ctDNA detection. Results: The results demonstrated that ctDNA was more frequently detected in patients with higher stage diseases pre- and postsurgery. Positive ctDNA detection at as early as 7 days postsurgery identified high-risk patients with recurrence (HR = 3.90, P < 0.001). Our results also show that longitudinal ctDNA monitoring of at least two postsurgical time points indicated a significantly higher risk (HR = 7.59, P < 0.001), preceding radiographic relapse in 73.5% of patients by a median of 145 days. Further, clonal ctDNA mutations indicated a high-level specificity, and subclonal mutations informed the origin of tumor recurrence. Conclusions: Longitudinal ctDNA surveillance integrating clonality information may stratify high-risk patients with disease recurrence and infer the evolutionary origin of ctDNA mutations. [ABSTRACT FROM AUTHOR]

0.8Mg2SiO4–0.2Ca0.9Sm0.2/3Al4x/3Ti1−xO3 (x = 0, 0.05, 0.1, 0.15, 0.2, and 0.25) ceramics with zero τf and high Q × f value were prepared by a traditional solid-state reaction method. The influences of Al content on phase evolution, sintering behavior, microstructure and microwave dielectric properties of ceramics have been systematically investigated. With the increase of x, the exchange of Ti4+ and Al3+ at B site leads to the decrease of dielectric constant and the increase of quality factor Q × f. The τf increases first and then decreases to close to 0 with a rise of x from 0.05 to 0.025. The results show that 0.8Mg2SiO4–0.2Ca0.9Sm0.2/3Al0.8/3Ti0.8O3 samples sintered at 1410 °C for 3 h exhibited excellent microwave dielectric properties: εr = 10.69, Q × f = 70,769 GHz, τf = − 0.66 ppm/°C. Therefore 0.8Mg2SiO4–0.2Ca0.9Sm0.2/3Al4x/3Ti1−xO3 ceramics are considered as potential candidates for microwave dielectric applications. [ABSTRACT FROM AUTHOR]

The practical applications of lithium-sulfur (Li-S) batteries are limited by the low conductivity of sulfur and the shuttle effect of soluble polysulfides during the charge-discharge process. At the same time, biomass-based carbon materials have been acknowledged as the cost-effective and direct settlement to mitigate or overcome these problems due to their renewability, facile processing, and pollution-free characteristics. Therefore, in this work, we report the natural nori-based CoO nanoparticles decorated hierarchical porous carbon (HPC) for high-capacity Li-S battery cathodes. The HPC with an extremely high surface area of 2089 m2 g−1 provides a good substrate for the accommodation of CoO nanoparticles, which can effectively seize the lithium polysulfides and facilitate their redox conversion. As a result, the CoO-HPC/S cathode exhibits a high discharge capacity of 1557.1 mA h g−1, as well as excellent rate performance and cycling stability. Due to the naturally abundant nori-based cathode materials, the resultant Li-S battery is supposed to be an attractive and sustainable energy storage device. [ABSTRACT FROM AUTHOR]

Adding a functionalized interlayer is one of the effective means to solve the problem of capacity attenuation caused by the shuttle of polysulfides in lithium–sulfur (Li–S) batteries. Moreover, the interlayer has the potential to take on more roles, such as having good mechanical flexibility to ensure high safety and flame-retardant property to improve the high temperature performance of the battery. Thus, in this work, an MXene/Co3O4–CNT film interlayer that is capable of dual chemisorption to polysulfides with good mechanical strength and flame retardancy has been investigated. The resultant Li–S battery assembled with this interlayer exhibits a high discharge capacity of 1569.5 mA h g−1, an excellent charge–discharge stability over 600 cycles, and a high temperature stability of the electrochemical performance. [ABSTRACT FROM AUTHOR]

In this work, (1−x)Mg2SiO4–xCa1−ySm2y/3TiO3 ceramics were fabricated using the conventional solid-state reaction method. When y = 0.2, the effects of Ca1−ySm2y/3TiO3 contents on microstructure, phase evolution, and microwave dielectric properties of the samples were studied. The X-ray diffraction showed that Mg2SiO4 and Ca0.8Sm0.4/3TiO3 co-existed in composite ceramics. The dielectric constant (εr) and temperature coefficient of resonant frequency (τf) increased with the increasing content of Ca0.8Sm0.4/3TiO3, while the quality factor (Q × f) decreased. At x = 0.22, the (1−x) Mg2SiO4–xCa0.8Sm0.4/3TiO3 ceramics sintered at 1325 °C for 3 h possessed optimal microwave dielectric properties: εr ~ 11.89, Q × f value ~ 32,703 GHz and τf ~ + 0.49 ppm/°C. As a result, the εr of (1−x) Mg2SiO4 + xCa1−ySm2y/3TiO3 ceramics could be adjusted in the range of 10.83 to 13.88 while the τf is near-zero. [ABSTRACT FROM AUTHOR]

The molten Na2CO3-assisted carbothermic reduction followed by water leaching is a promising process to comprehensively utilize the titanomagnetite concentrate. In this study, the effects of temperature, graphite component, and Na2CO3 component on the iso-carbothermic reduction of titanomagnetite in argon atmosphere were investigated. Thermodynamic analysis results speculated reduction of iron oxides in titanomagnetite concentrate in Na-Fe-Ti-C-O system at 1423 K to 1523 K were feasible, and low-valence titanium oxide was not formed with the existence of Na2O. The iso-reaction mechanisms and kinetic analyses of Na2CO3-titanomagnetite, Na2CO3-graphite, graphite-titanomagnetite, and Na2CO3-graphite-titanomagnetite were investigated at 1523 K. In the roasting process of Na2CO3 and titanomagnetite, Na2CO3 destroyed the crystal structure of titanomagnetite and oxidized Fe2+ to Fe3+, generating CO gas. Thus, with the assistance of Na2CO3, the carbothermic reduction rate of titanomagnetite was expedited. Compared with the direct reduction process, after adding Na2CO3, the apparent reduction activation energy of iron oxides decreased from 165.56 to 87.25 kJ·mol−1. [ABSTRACT FROM AUTHOR]

Ceramic/polymer nanocomposites have been extensively explored for dielectric capacitor application due to their high energy storage performance and ease of processing, flexibility, and low cost. However, improving compatibility between inorganic and organic materials is of great significance and has been a long‐standing challenge. In this work, the polymer surfactant Pluronic™ F127 was employed to perform surface modification of BaTiO3 through a facile solution process. The compatibility between BaTiO3 nanoparticles and P (VDF‐HFP) can be remarkably strengthened by the affinity between F127 polymer chains and the organic matrix. Structural defects such as pores, cracks, and agglomeration of inorganic particles were obviously reduced, and interfacial polarization has been significantly enhanced. The discharged energy density Ud and charge–discharge efficiency η reach up to 5.0 J/cm3 and 58.1% under the breakdown strength of 3740 kV/cm for the nanocomposite containing 1 vol% BT@F127. These dielectric properties are clearly better than the nanocomposite using unmodified BT, as well as similar hybrids reported previously. [ABSTRACT FROM AUTHOR]

The alumina/glass fibers cloth/polytetrafluoroethylene composites were prepared by blending impregnation followed by hot compression method, and the dielectric, thermal, and mechanical properties of the composites with various Al2O3 contents (15–40 wt%) were investigated. The results show that the thermal conductivity and dielectric constant of the composites increase gradually, while the coefficient of thermal expansion decreases, with the Al2O3 content increasing. Composite substrates with 40 wt% Al2O3 exhibited ideal performance, which have reliable dielectric constant (εr = 3.49), admissible dielectric loss (tanδ = 0.0027), low water absorption (0.04 %), low CTE of 8.73, 10.14 and 110.39 ppm/°C (X-, Y-, Z-direction, respectively), relatively high thermal conductivity (0.61 W m−1 K−1), and satisfactory flexural strength (66.1 MPa). Such compositions may be a promising material in high-frequency microwave substrates. [ABSTRACT FROM AUTHOR]

Costunolide (cos) derived from the roots of Dolomiaea souliei (Franch.), which belongs to the Dolomiaea genus in the family Compositae, exert the anti‐inebriation effect mainly by inhibiting the absorption of alcohol in the gastrointestinal tract. However, the protective effect of cos against alcohol‐induced liver injury (ALI) remains obscure. The present study was aimed to evaluate the hepatoprotective effects of cos (silymarin was used as positive control) against ALI and its potential mechanisms. MTT was used to examine the effect of cos on the cell viability of L‐02 cells. Plasma was separated from blood that used to test the levels of TNF‐α, IL‐6 and IL‐12, and LPS while serum separated from blood which used to detect the level of ALT and AST. Liver tissues were obtained for histopathological examination and western blot analysis. Fresh mice feces samples were collected for the detection of bacterial composition. Cos exhibited protective effect against alcoholic‐induced liver injury by regulating gut microbiota capacities (higher relative abundance of Firmicutes and Actinobacteria while lower in Bacteroidetes and Proteobacteria), adjusting oxidative stress (reduced the activities of MDA and ROS while promoted SOD, GSH and GSH‐PX in L‐02 cells) and attenuating inflammation (decreased the levels of ALT, AST, LPS, IL‐6, IL‐12 and TNF‐α) via LPS‐TLR4‐NF‐κB p65 signaling pathway, which might be an active therapeutic agent for treatment of ALI. [ABSTRACT FROM AUTHOR]

To reduce Ti-bearing blast furnace slag wastage, our group previously developed a metallurgical process in which Ti-bearing slag was produced using Na2CO3 instead of CaO. This process increased the TiO2 content—in the form of Na2Ti16O33 (40.93%) and CaTiO3 (42.77%)—of the slag from 22% to ~43%. In this report, a method based on the use of sulfuric–chloric mixture acid (SCMA) is proposed for slag decomposition, and a decomposition rate of ~80% is achieved. After hydrothermal hydrolysis, at a titanium concentration of 1.1-1.4 mol·L−1, the titanium conversion is > 90%, and uniform particle sizes of metatitanic acid (2-4 µm) are produced. The mechanism for decomposition process is based on two-stage kinetics and is controlled through diffusion of Ti–Na and Ti–Ca. SCMA method is more economic and environmentally friendly than existing methods because of an energy-efficient decomposition process and acid recycling. [ABSTRACT FROM AUTHOR]

The carbothermic reduction of vanadium titanomagnetite concentrate (VTC) with the assistance of Na2CO3 was conducted in an argon atmosphere between 1073 and 1473 K. X-ray diffraction and scanning electron microscopy were used to investigate the phase transformations during the reaction. By investigating the reaction between VTC and Na2CO3, it was concluded that molten Na2CO3 broke the structure of titanomagnetite by combining with the acidic oxides (Fe2O3, TiO2, Al2O3, and SiO2) to form a Na-rich melt and release FeO and MgO. Therefore, Na2CO3 accelerated the reduction rate. In addition, adding Na2CO3 also benefited the agglomeration of iron particles and the slag—metal separation by decreasing the viscosity of the slag. Thus, Na2CO3 assisted carbothermic reduction is a promising method for treating VTC at low temperatures. [ABSTRACT FROM AUTHOR]

Embedding heteroatoms into the main backbones of polymeric materials has become an efficient tool for tailoring their structures and improving their properties. However, owing to comparatively harsh heteroatom‐doping conditions, this has rarely been explored in covalent organic frameworks (COFs). Herein, upon aldol condensation of a trimethyl‐substituted pyrylium salt with a tritopic aromatic aldehyde, a two‐dimensional oxonium‐embedded COF with vinylene linkages was achieved, which was further converted to a neutral pyridine‐cored COF by in situ replacement of oxonium ions with nitrogen atoms under ammonia treatment. The two heteroatom‐embedded COFs are conceptually isoelectronic with each other, featuring similar geometric structures but different electronic structures, rendering them capable of catalyzing the visible‐light‐promoted multi‐component synthesis of tri‐substituted pyridine derivatives with good recyclability. [ABSTRACT FROM AUTHOR]

Embedding heteroatoms into the main backbones of polymeric materials has become an efficient tool for tailoring their structures and improving their properties. However, owing to comparatively harsh heteroatom‐doping conditions, this has rarely been explored in covalent organic frameworks (COFs). Herein, upon aldol condensation of a trimethyl‐substituted pyrylium salt with a tritopic aromatic aldehyde, a two‐dimensional oxonium‐embedded COF with vinylene linkages was achieved, which was further converted to a neutral pyridine‐cored COF by in situ replacement of oxonium ions with nitrogen atoms under ammonia treatment. The two heteroatom‐embedded COFs are conceptually isoelectronic with each other, featuring similar geometric structures but different electronic structures, rendering them capable of catalyzing the visible‐light‐promoted multi‐component synthesis of tri‐substituted pyridine derivatives with good recyclability. [ABSTRACT FROM AUTHOR]

Conductive carbon structure has been considered as a promising sulfur-hosting material as the cathode of lithium-sulfur batteries. However, the issue of polysulfide shuttling requires an additional component to help restrict and convert sulfur substances. Herein, in this work, hollow and porous carbon nanospheres (HCS) are synthesized by a template method and a high-temperature carbonization treatment. A thin layer of ZnS coating is then deposited on the HCS-based sulfur (ZnS@HCS/S) cathode with controlled thickness, and the overall electrochemical properties are systematically evaluated. Results show that with 30 nm-thick ZnS coating, the cathode reveals an improved capacity of 1411 mA h g−1, and higher capacities from 0.2 to 3 C rate compared with bare HCS/S cathode. Moreover, the ZnS coating also enhances the cycling stability of ZnS@HCS/S cathode over 280 cycles at 0.5 C, with only 0.2% capacity decay per cycle. This work demonstrates potential applications for high-performance lithium-sulfur batteries. [ABSTRACT FROM AUTHOR]

The effects of injecting TiO2 to a Li2O–MgO–ZnO–B2O3–SiO2 (LMZBS) microwave dielectric composite on sinterability, microstructure, crystalline phase, dielectric characteristics, mechanical characteristics, and coefficient of thermal expansion (CTE) were investigated. With the increase of TiO2 content, the main crystal orientation of the samples gradually changed from Li2MgSiO4 phase, Mg3B2O6 phase, and Mg2SiO4 phase to Li5.48Mg0.74Ti7.26O18, ZnTiO3 phase, and Mg2B2O5 and the densification temperature decreased, whisker-like crystal grains gradually increased, and the porous microstructure appeared at 15% TiO2. With the increase of TiO2 content, the densification temperature of LMZBS ceramics increases, and the dielectric constant increases with the increase of densification temperature. The CTE value decreases with the increase of titanium dioxide content, and the bending strength increases first and then decreases with the increase of titanium dioxide content. The composite with 10 wt% TiO2 content sintered at 900 °C exhibits superior performance: ε r of 7.97, Q value of 1305 (10 GHz), flexural strength of 259 MPa, CTE value of 10.2 ppm/°C, and τ f value of − 13 ppm/°C. The LMZBS/TiO2 composites are suitable for LTCC application with match-well Ag electrodes. [ABSTRACT FROM AUTHOR]