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Long-period comets C/2019 L3 (ATLAS) and C/2020 P3 (ATLAS) remain active at heliocentric distance greater than 4 au. Broad-band Charge-Coupled Device (CCD) photometry of long-period comets C/2019 L3 and C/2020 P3 is analysed in this paper. The observation was obtained with three telescopes: ZEISS-1000 at Simeiz Observatory, Maksutov at Abastumani Astrophysical Observatory, and ZTSh at Crimean Astrophysical Observatory. The R -band A (0) f ρ values of C/2019 L3 range from (5043 ± 244) to (13611 ± 1874) cm, and tend to decrease first and then increase. The average colour indices of C/2019 L3 are B – V = 0.75 ± 0.06, V – R = 0.28 ± 0.05, and R – I = 0.21 ± 0.05. The reddening of C/2019 L3 exhibits variations during the observational runs, ranging from (13.75 ± 1.07) to (−15.69 ± 0.37) per cent/kÅ with an average value of (0.94 ± 0.23) per cent/kÅ. It possesses a non-steady coma since the average gradient of its surface brightness profile is −1.60. For comet C/2020 P3, its R -band A (0) f ρ values range from (606 ± 31) to (869 ± 20) cm, the colour indices are B–V = 1.04 ± 0.09, V–R = 0.26 ± 0.05, and R – I = 0.76 ± 0.04, and the reddening is (−6.65 ± 0.01) per cent/kÅ. The colour indices of the two comets differ from those of other long-period comets. Compared with other long-period comets, comet C/2019 L3 is very active at heliocentric distance of ∼4 au, while C/2020 P3 is moderately active at heliocentric distance of ∼7 au. [ABSTRACT FROM AUTHOR]

As a key factor affecting the performance of supercapacitors, the research on electrode materials for supercapacitors has been primarily focused on the cathode with little work found on anode materials. This has hindered the improvement of the energy density of supercapacitors. The objective of this work, therefore, was to prepare a high-performance, low-cost anode material for supercapacitors. Fe3O4 was synthesized by a hydrothermal method and Fe3O4/rGO nanocomposites were prepared by further hydrothermal treatment of Fe3O4 with graphene oxide. The Fe3O4/rGO nanocomposites were characterized by XRD, SEM, TEM, BET. and other methods to analyze their micromorphology and elemental composition. Electrochemical measurements were performed to assess the electrochemical properties of Fe3O4/rGO, which was tested with a high specific capacitance of 571.2 F g−1 (1 A g−1), much higher than that of pure Fe3O4 (214.7 F g−1). Assembling Fe3O4/rGO//MnO2 asymmetric supercapacitors (ASC) with MnO2 as the positive electrode and Fe3O4/rGO as the negative electrode, the device obtained an energy density of 95.1 Wh kg−1 at a power density of 2881 W kg−1. After 10,000 cycles at 10 A g−1, the ASC retained 87.2% of its original capacitance, so the Fe3O4/rGO nanocomposite could be an ideal anode material for high-performance supercapacitors. [ABSTRACT FROM AUTHOR]

Although there have been many studies on asymmetric supercapacitors (ASCs), anode materials are still mainly carbon-based. However, carbon-based materials with low specific capacitance cannot match the cathode materials, limiting the energy density of ASCs. In this research, a low-cost and environmentally friendly anode of homogeneous α-Fe2O3 nanoparticles grown on three-dimensional graphene (3DG) hydrogel is synthesized, with significant specific capacitance (788.6 F g−1 at 1 A g−1) and exceptionally good stability (retaining 82.3% capacitance after 5000 cycles). The composite material of NiCo2O4 nanorods grown on 3DG (NiCo2O4/3DG) has been prepared as the cathode by a similar method. The NiCo2O4/3DG also shows excellent electrochemical performance (1264.3 F g−1 at 1 A g−1 and stability of 91.7% after 5000 cycles). Furthermore, the ASCs of NiCo2O4/3DG//α-Fe2O3/3DG, which is composed of the as-prepared cathode and anode materials, exhibits excellent energy density of 77.8 W h kg−1 at a power density of 800 W kg−1, and outstanding stability of 81.6% after 5000 cycles at 10 A g−1. Therefore, this proves that α-Fe2O3/3DG is a promising anode material for supercapacitors. [ABSTRACT FROM AUTHOR]

Both EGFR and VEGFR-2 play a critical role in tumor growth, angiogenesis and metastasis, and targeting EGFR and VEGFR-2 simultaneously represents a promising approach to cancer treatment. In this work, a series of novel quinazoline- and thiourea-containing sorafenib analogs (10a-v) were designed and synthesized as EGFR and VEGFR-2 dual TK inhibitors. Their in vitro enzymatic inhibitory activities against EGFR and VEGFR-2, and antiproliferative activities against HCT-116, MCF-7 and B16 cell lines were evaluated and described. Most of the compounds showed potent activities against both cell lines and TK kinases. Compounds 10b and 10q which exhibited the most potent inhibitory activities against EGFR (IC50 = 0.02 µM and 0.01 µM, respectively), VEGFR-2 (IC50 = 0.05 µM and 0.08 µM, respectively), and good antiproliferative activities, also displayed competitive anti-tumor activities than sorafenib in vivo by B16 melanoma xenograft model test. [ABSTRACT FROM AUTHOR]