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This study proposes a simple modification method of sepiolite based on inorganic liquid (which contains hydrochloric acid, sodium chloride and sodium hexametaphosphate), and the modified sepiolite (as@sep) is used to remove Pb2+ in aqueous solution. More importantly, this study optimized the modification conditions of sepiolite by the response surface method (RSM), and the results showed that the optimized as@sep had significantly higher adsorption capacity for Pb2+ than that before modification (the adsorption capacity before and after modification were 19.04 and 31.81 mg g-1, respectively). A series of characterizations combined with adsorption kinetics and thermodynamics analysis revealed the adsorption mechanism of as@sep for Pb2+. The analysis results show that the adsorption of as@sep to Pb2+ is mainly carried out by ion exchange, surface hydroxyl complexation, pore filling and electrostatic attraction, and this adsorption reaction is a spontaneous exothermic process in low temperature. The above positive results indicate the superiority of the facile modification strategy of sepiolite proposed in this study. [Display omitted] [ABSTRACT FROM AUTHOR]

• Explored eleven potential ligands in AP against COX-2, IL-6 and ACE2. • Verified some potent ligands in AP with bioassays and molecular docking. • Constructed the first interaction network to unveil the empirical use of AP. Andrographis paniculata (Burm. F.) Nees (AP) was a typical plant resource that has the concomitant function of both foodstuff and medicine, while the action mechanisms of its immune regulation, anti-inflammatory and anti-viral effects and the specific components remain unclear. In this work, a screening approach combining bio-affinity ultrafiltration with liquid chromatography mass spectrometry (UF-LC/MS) was hired to screen potential bioactive compounds from AP. The crude extract of AP exerted COX-2 and ACE2 inhibitory effects by other bioassays. Meanwhile, a total of eleven ligands targeting COX-2, IL-6 and ACE2 were screened out. Thereinto, two compounds including andrographolide and 14-deoxy-11,12-didehydroandrographolide exhibited strong binding affinities to COX-2, IL-6 and ACE2 by UF-LC/MS and molecular docking analysis. This is the first report to apply UF-LC/MS approach to rapidly screen out multi-target ligands from AP, and further decipher corresponding mechanisms, which could be beneficial to expedite the search for new multi-target bioactive compounds in other natural products or foods. [ABSTRACT FROM AUTHOR]

Abstract: We report a facile and effective method for synthesizing polypyrrole/modified graphite oxide (PPy/MGO) composites by in situ polymerization. The graphite oxide (GO) is modified with hexadecylpyridinium chloride (CPC) and then composited with PPy. Scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR) results demonstrate that PPy chains may combine with CPC molecule via π–π stacking interaction and the structures of PPy/GO and PPy/MGO composites are completely different. Cyclic voltammetry (CV), galvanostatic charge–discharge (GCD), and electrochemical impedance spectrum (EIS) tests indicate that, at the current density of 1 A g−1, the specific capacitance and energy density of PPy/MGO are 202 F g−1 and 8.49 Wh kg−1 in three-electrode systems and those are 87 F g−1 and 10 Wh kg−1 in two-electrode systems; the capacitance retention of PPy/MGO is 83.8% after 1000 cycles at a scan rate of 1 A g−1; PPy/MGO also exhibited excellent energy performance from Ragone charts. Based on these properties, the PPy/MGO composites may become a promising material for supercapacitor applications. [Copyright &y& Elsevier]

In recent years, magnetic metal nanoparticles (NPs)/carbon nanofibers (CNFs) composites have become very promising electromagnetic waves (EMWs) absorbers. However, how to achieve controllable growth of magnetic metals in CNFs is still an urgent problem to be solved. Herein, we reported a pore-confined strategy for constructing the porous Co/CoO/CNFs. By introducing different amounts of acetone (0.20 g, 0.30 g and 0.40 g) into the aqueous phase spinning solution to construct the porous structure, we achieved uniform distribution of Co/CoO NPs and ultimately obtained the porous Co/CoO/CNFs microwave absorbers (MAs) with excellent microwave absorption performance. Thanks to the excellent impedance matching and enhanced polarization loss, the porous Co/CoO/CNFs obtained the minimum reflection loss (RL) of −52.2 dB with a thickness of 3.0 mm, and the effective bandwidth (EBW) was 3.02 GHz when the acetone addition in the spinning solution was 0.30 g. Therefore, the pore-confined strategy proposed herein is conducive to the design of the MAs with excellent performance and low infilling rates based on CNFs. Furthermore, the porous structure of CNFs also improves the lightweight performance of the MAs. [ABSTRACT FROM AUTHOR]

Due to their physicochemical properties, the three-dimensional Metal-organic frameworks (MOFs) derived composites show great potential as electromagnetic wave (EMW) absorbers. However, poor impedance matching limits their actual EMW absorption performance. Composite materials that combine magnetic and dielectric losses offer a potential solution to enhance impedance match and significantly improve microwave absorption. In this work, a novel N,S-GS/Co/C composite was fabricated via a solvothermal method and a subsequent pyrolysis process to introducing nitrogen and sulfur co-doped graphene (N,S-GS) into Co-MOF. By co-doping nitrogen and sulfur, abundant defects and disordered sites were introduced on graphene, which stimulate interfacial polarization and dipole polarization. The minimum reflection loss (RL) of the sample obtained by pyrolysis at 600 °C is −68.8 dB at 9.7 GHz. Simultaneously, the thickness is 2.51 mm, and the effective absorption bandwidth (EAB) can reach 3.04 GHz. Its excellent EMW absorption performance is mainly attributed to interfacial polarization, multiple reflections, dipole polarization, magnetic resonance and eddy current loss. Accordingly, the N,S-GS/Co/C composite is convinced to be a competent candidate among EMW absorbers with high absorption intensity. [ABSTRACT FROM AUTHOR]

MnO 2 /carbon nanowires composites (CNWMn) have been prepared through a simple hydrothermal method using carbon nanowires (CNW) as the both reducing agents and scaffolds for MnO 2 growth. The crystalline phase of CNWMn is closely related to the hydrothermal reaction time, which has a profound impact on the electrochemical performance of CNWMn composites. Typically, the CNMWn2 (reaction time is 2 h) exhibits a highest specific capacitance of 465 F g −1 at the current density of 1 A g −1 in three-electrode systems. In addition, a two-electrode asymmetric system has also been fabricated using CNWMn2 and porous carbon nanowires (PCNW) as positive and negative electrode, respectively. The asymmetric system presents a maximum energy density of 39.2 Wh kg −1 at the current density of 0.5 A g −1 , which is much higher than that of traditional sense supercapacitors. Moreover, the asymmetric system exhibits excellent rate capability (high energy density of 24.2 Wh kg −1 at the current density of 10 A g −1 ) and high cycle stability with only 7% loss of its initial capacitance after 2000 cycles. [ABSTRACT FROM AUTHOR]

Nitrogen-doped porous carbon nanowires were prepared by KOH activation of nitrogen doped carbon nanowires derived from direct carbonization of polypyrrole nanowires. The porous structure and nitrogen content were closely related to the mass ratio of KOH and carbon nanowires. The resultant nanowires demonstrated the highest specific surface area (1642 m 2 g −1 ) and capacitance (291 F g −1 at the current density of 1 A g −1 in three-electrode systems), when the mass ratio of KOH and nitrogen doped carbon nanowires reached 2. It also exhibited the excellent high rate performance and good cycle stability (94.8% capacitance retention after 5000 cycles) in three-electrode systems. High energy density (21.9 Wh kg −1 at a current density of 0.4 A g −1 in 0-1.6 V) and good cycle stability (the capacitance retention of 98.1% over 5000 cycles) were shown in symmetric two-electrode systems. These excellent electrochemical performances could be attributed to the high surface area, unique micro/meso/macroporous structure, and optimized nitrogen content. [ABSTRACT FROM AUTHOR]

Phenol-formaldehyde resin (PFR) has been synthesized in a reaction catalyzed with NaOH. The molecular structures of PFR were investigated using Fourier transform infrared spectroscopy (FTIR) and high performance liquid chromatography-mass spectrometry (HPLC-MS). In this study, the size of PFR aggregates were measured by a dynamic light scattering technique (DLS) in order to elucidate the dispersion performance of PFR dispersed in water. The coagulation behavior of the PFR aggregates with various pH values, valences and concentrations of H+ were investigated using DLS. The highest coagulation rate (ddt) at different pH values followed the order of: acidic > alkaline, which can be explained by the effects of electrostatic repulsion at protonation states of phenolic –OH groups. The coagulation phenomenon appeared at pH values less than 7. The fractal dimension d f ≈ 2.1 could be determined for reaction-linked colloid aggregation (RLCA) when pH < 7. These results indicated that PFR had a coagulation behavior which could be exploited in enhanced oil recovery (EOR) processes. [ABSTRACT FROM AUTHOR]