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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]

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]

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]

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 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]

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]

Five previously undescribed flavonoids (1–5) and ten known ones (6–15) were isolated from the roots of Oxybaphus himalaicus. Their structures were elucidated by spectroscopic experiments including NMR, HRESIMS and ECD. The cytotoxic activities of all isolated compounds were assayed against human lung carcinoma A549 cells and human hepatocellular carcinoma HepG2 cells in vitro. Compound 11 displayed the most powerful inhibitory effect with IC50 values of 19.47 ± 0.28 μM against A549 and 52.6 ± 0.38 μM against HepG2, respectively. [ABSTRACT FROM AUTHOR]

Two new cycloartane glycosides, cycloatriosides A and B (1–2), and a new oleanolic acid glycoside, thaliatrioside A (3), along with 7 known triterpenoids (4–10) were isolated from Thalictrum atriplex. The structures of the new compounds were established as 3-O-β-D-galactopyranosyl (20S, 24 R)-3β,16β,25,29-tetrahydroxy-20,24-epoxycycloartane-29-O-β-D-glucopyranoside (1), 3-O-β-D-glucopyranosyl-(1→2)-α-arabinopyranosyl-3β,22ξ,30-trihydroxycycloart-24-en-21-oic acid α-L-arabinopyranosyl-(1→6)-β-D-glucopyranoside (2) and 3-O-[α-L-rhamnopyranosyl-(1→3)-β-D-xylopyranosyl-(1→3)-α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranosyl]-oleanolic acid 28-O-β-D-glucopyranosyl ester (3) on the basis of extensive NMR and HR-ESI-MS analyses, along with acid hydrolysis. Their cytotoxic activities against human lung cancer cells A549 and human breast cancer cells MDA-MB-231 were evaluated using MTT method. Compound 9 showed cytotoxicity against MDA-MB-231 cell line with the IC50 value of 72.53 ± 1.08 μM. [ABSTRACT FROM AUTHOR]

The alumina/hexagonal boron nitride/glass fibers cloth/Polytetrafluoroethylene (Al2O3–hBN/GFs/PTFE) composites were prepared by blending-impregnation followed by hot compression method, and the dielectric, thermal properties of the composites with various hBN fillers content (0–20 wt.%) were investigated. The results show that the thermal conductivity of the composites increase significantly, while the coefficient of thermal expansion (CTE) decrease gradually, with the hBN content increasing. Composite substrates with 20 wt.% hBN exhibited high thermal conductivity as 1.05 W m−1 K−1, which is 5.3 times that of pure PTFE. Such compositions may be a promising material in high thermal conductivity copper clad laminate. [ABSTRACT FROM AUTHOR]

In order to improve the thermal properties of polytetrafluoroethylene (PTFE) as a high-frequency microwave dielectric substrate, PTFE/glass fiber (GF) composites filled with Si3N4 were prepared by the method of combining cold pressing and normal pressure sintering. The effects of content of Si3N4 on microstructure, thermal and dielectric properties of the PTFE/GF composites were studied by scanning electron microscope, laser thermal conductivity analyzer, thermal dilatometer and impedance analyzer, respectively. The results showed that silane coupling agent (KH550) could improve the dispersibility of the Si3N4 particles in PTFE to some extent and Si3N4 fillers could significantly improve the thermal properties of PTFE. Compared with pure PTFE, the coefficient of thermal expansion of PTFE/GF composite filled with 45wt% Si3N4 decreased from 109 to 27 ppm/°C and the thermal conductivity increased nearly twice. The dielectric constant of PTFE/GF composites grew with the content of Si3N4 and had good frequency stability. Although the dielectric loss of the composites deteriorated with the addition of Si3N4, it was significantly decreased with increasing frequency, indicating that there is a potential application of Si3N4 filled PTFE/GF composites in the field of high-frequency dielectric substrate. [ABSTRACT FROM AUTHOR]

A micro-nano structure CaF 2 chemical conversion layer was prepared on fluoride-treated AZ31 alloy, then the composite fluoride conversion film (CaF 2 /MgF 2) was modified by stearic acid (SA) and fabricated a superhydrophobic surface. The fluoride-treated magnesium, fluoride conversion film and superhydrophobic coating were characterized by SEM, EDS, XRD and FTIR. The properties of coatings' adhesion and corrosion resistance were evaluated via tape test and electrochemical measurement. The cytocompatibility of the MgF 2 , CaF 2 and super-hydrophobic CaF 2 /SA surface was investigated with bone marrow-derived mesenchymal stem cells (BMSCs) by direct culture for 24 h. The results showed that the superhydrophobic fluoride conversion coating composed of inner MgF 2 layer and the outer CaF 2 /SA composite layer had an average water contact angle of 152°. SA infiltrated into the micro-nano structure CaF 2 layer and formed a strong adhesion with CaF 2 layer. Furthermore, the super-hydrophobic coating showed higher barrier properties and corrosion resistance compared with the fluoride conversion film and fluoride-treated AZ31 alloy. The BMSC adhesion test results demonstrated MgF 2 CaF 2 and CaF 2 /SA coatings were all nontoxic to BMSC. At the condition of in direct contact with cells, MgF 2 showed higher cell density and enhanced the BMSCs proliferation, while CaF 2 and CaF 2 /SA coating showed no statistically difference in cell density compared with glass reference but the CaF 2 and CaF 2 /SA coating were not conducive to BMSCs adhesion. [ABSTRACT FROM AUTHOR]

Irinotecan (CPT-11) is used as chemotherapeutic drug for treatment of colorectal cancer. However, without satisfactory treatments, its gastrointestinal toxicities such as diarrhea and intestinal inflammation severely restrained its clinical application. Roots of Aucklandia lappa Decne. are used as traditional Chinese medicine to relieve gastrointestinal dysfunction and dehydrocostus lactone (DHL) is one of its main active components. Nevertheless, the efficacy and mechanism of DHL against intestinal mucositis remains unclear. The present study aimed to investigate the protective effects of DHL on CPT-11-induced intestinal mucositis and its underlying mechanisms. The protective effect of DHL was investigated in CPT-11-induced mice and lipopolysaccharide (LPS)+CPT-11 induced THP-1 macrophages. Body weight, diarrhea score, survival rate, colon length, and histopathological changes in mice colon and jejunum were analyzed to evaluate the protective effect of DHL in vivo. And DHL on reducing inflammatory response and regulating TLR4/NF‐κB/NLRP3 pathway in vivo and in vitro were explored. Moreover, DHL on the interaction between TLR4 and MD2 was investigated. And silencing TLR4 targeted by siRNA was performed to validate the mechanisms of DHL on regulating the inflammation. DHL prevented CPT-11-induced intestinal damage, represented by reducing weight loss, diarrhea score, mortality rate and the shortening of the colon. Histological analysis confirmed that DHL prevented intestinal epithelial injury and improved the intestinal barrier function in CPT-11 induced mice. Besides, DHL significantly downregulated the level of inflammatory cytokines by inhibiting TLR4/NF-κB/NLRP3 signaling pathway in CPT-11-induced mice and LPS+CPT-11-induced THP-1 macrophages. In addition, DHL blocked TLR4/MD2 complex formation. Molecular docking combined with SIP and DARTS assay showed that DHL could bind to TLR4/MD2 and occludes the hydrophobic pocket of MD2. Furthermore, Silencing TLR4 abrogated the effect of DHL on LPS+CPT-11 induced inflammatory response in THP-1 macrophages. Additionally, DHL ameliorate the CPT-11-induced intestinal mucositis without affecting the anti-tumor efficacy of CPT-11 in the tumor xenograft mice. This study found that DHL exhibited the anti-inflammatory effects in CPT-11-induced intestinal mucositis by inhibiting the formation of TLR4/MD2 complex and then regulation of NF-κB/NLRP3 signaling pathway. DHL is potentially served as a novel strategy of combined medication with CPT-11. [ABSTRACT FROM AUTHOR]