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We report the results of long-term reverberation mapping (RM) campaigns of the nearby active galactic nuclei (AGN) NGC 4151, spanning from 1994 to 2022, based on archived observations of the FAST Spectrograph Publicly Archived Programs and our new observations with the 2.3m telescope at the Wyoming Infrared Observatory. We reduce and calibrate all the spectra in a consistent way, and derive light curves of the broad H$\beta$ line and 5100\,{\AA} continuum. Continuum light curves are also constructed using public archival photometric data to increase sampling cadences. We subtract the host galaxy contamination using {\it HST} imaging to correct fluxes of the calibrated light curves. Utilizing the long-term archival photometric data, we complete the absolute flux-calibration of the AGN continuum. We find that the H$\beta$ time delays are correlated with the 5100\,{\AA} luminosities as $\tau_{\rm H\beta}\propto L_{5100}^{0.46\pm0.16}$. This is remarkably consistent with Bentz et al. (2013)'s global size-luminosity relationship of AGNs. Moreover, the data sets for five of the seasons allow us to obtain the velocity-resolved delays of the H$\beta$ line, showing diverse structures (outflows, inflows and disks). Combining our results with previous independent measurements, we find the measured dynamics of the H$\beta$ broad-line region (BLR) are possibly related to the long-term trend of the luminosity. There is also a possible additional $\sim$1.86 years time lag between the variation in BLR radius and luminosity. These results suggest that dynamical changes in the BLR may be driven by the effects of radiation pressure., Comment: Accepted for publication in MNRAS; comments welcome!

Heng Li,1 Ying-Jie Wang,1 Xiao-Nan Geng,1 Yao-Ren Kang,1 Yi-Lin Wang,1 Xiang-Jun Qiu1,2 1Department of Pharmacy, School of Basic Medical Sciences, Henan University of Science and Technology, Luoyang, 471023, People’s Republic of China; 2Functional Experiment Teaching Center, School of Basic Medical Sciences, Henan University of Science and Technology, Luoyang, 471023, People’s Republic of ChinaCorrespondence: Xiang-Jun Qiu, Functional Experiment Teaching Center, School of Basic Medical Sciences, Henan University of Science and Technology, 263 Kaiyuan Avenue, Luoyang, 471023, Henan, People’s Republic of China, Email lyxiangjun@126.comObjective: A sensitive and rapid UPLC-MS/MS method for determination of tazemetostat in rat plasma was developed, and the pharmacokinetics of herb-drug interactions (HDIs) of plumbagin (PLB) and tazemetostat was investigated.Methods: After the rat plasma samples were precipitated by acetonitrile, tazemetostat and verubecestat (ISTD) were detected. Gradient elution was performed with 0.1% formic acid and acetonitrile as mobile phases. The multi-reaction monitoring was used with ESI+ source, and the ion pairs for tazemetostat and ISTD were m/z 573.12→ 135.99 and m/z 410.10→ 124.00, respectively. 12 SD rats were randomly divided into the control group and the experimental group, 6 rats in each group. The rats in the experimental group were given PLB 100 mg/kg by gavage once a day for 7 consecutive days. The rats in the control group were given the same amount of 0.1% sodium carboxymethyl cellulose solution by gavage once a day for 7 consecutive days. At the seventh day, tazemetostat (80 mg/kg) was given and the blood was collected at different time points. The main parameters of pharmacokinetics were calculated and the herb-drug interactions (HDIs) were evaluated.Results: In the calibrated range of 1– 1000 ng/mL, tazemetostat had a good linearity. The extraction recovery was more than 84%, and the RSD of intra-batch and inter

The mineralogical characteristics of three kinds of gibbsitic high-iron bauxite and the effects of various digestion conditions on the enrichment and separation of iron minerals were investigated. The results show that adding an appropriate organic reductant such as glycerol can promote the digestion of concomitant diaspore, boehmite and alumogoethite as well as the conversion of goethite to haematite in the reductive Bayer digestion. Processing bauxite A with Al/Si ratio of 25.41 can directly produce qualified iron concentrates (total Fe more than 56%) by reductive Bayer digestion, and thus realise zero red mud discharge. For bauxite B and bauxite C with Al/Si of 7.82 and 3.35, Fe recoveries of 65.13% and 79.13% can be achieved with the corresponding TFe of 52.05% and 50.16% in the iron concentrates by gravity separation, respectively, resulting in a red mud discharge reduction of c.50% or above. (Authors. ), The mineralogical characteristics of three kinds of gibbsitic high-iron bauxite and the effects of various digestion conditions on the enrichment and separation of iron minerals were investigated. The results show that adding an appropriate organic reductant such as glycerol can promote the digestion of concomitant diaspore, boehmite and alumogoethite as well as the conversion of goethite to haematite in the reductive Bayer digestion. Processing bauxite A with Al/Si ratio of 25.41 can directly produce qualified iron concentrates (total Fe more than 56%) by reductive Bayer digestion, and thus realise zero red mud discharge. For bauxite B and bauxite C with Al/Si of 7.82 and 3.35, Fe recoveries of 65.13% and 79.13% can be achieved with the corresponding TFe of 52.05% and 50.16% in the iron concentrates by gravity separation, respectively, resulting in a red mud discharge reduction of c.50% or above. (Authors. )

Low-temperature scanning tunneling microscope (STM) is exploited to study directly the atomic and electronic structures of single Fe dopants in topological insulator Bi2Se3 thin films. Fe atoms predominantly and isovalently substitute for two distinct Bi sites at the subsurface with charge neutrality. In the vicinity of Fe substitutions, circular depressions in STM topography and sharp rings in spatially resolved conductance map, whose diameters apparently depend on the tunneling conditions, are observed. We show that the phenomena correlate well with the switching between Fe3+ and Fe2+ charge states due to the gate effect of the tunneling tip, as further evidenced by a multidopant system.

Low-temperature scanning tunneling microscope (STM) is exploited to study directly the atomic and electronic structures of single Fe dopants in topological insulator Bi2Se3 thin films. Fe atoms predominantly and isovalently substitute for two distinct Bi sites at the subsurface with charge neutrality. In the vicinity of Fe substitutions, circular depressions in STM topography and sharp rings in spatially resolved conductance map, whose diameters apparently depend on the tunneling conditions, are observed. We show that the phenomena correlate well with the switching between Fe3+ and Fe2+ charge states due to the gate effect of the tunneling tip, as further evidenced by a multidopant system.

Low-temperature scanning tunneling microscope (STM) is exploited to study directly the atomic and electronic structures of single Fe dopants in topological insulator Bi2Se3 thin films. Fe atoms predominantly and isovalently substitute for two distinct Bi sites at the subsurface with charge neutrality. In the vicinity of Fe substitutions, circular depressions in STM topography and sharp rings in spatially resolved conductance map, whose diameters apparently depend on the tunneling conditions, are observed. We show that the phenomena correlate well with the switching between Fe3+ and Fe2+ charge states due to the gate effect of the tunneling tip, as further evidenced by a multidopant system.

Low-temperature scanning tunneling microscope (STM) is exploited to study directly the atomic and electronic structures of single Fe dopants in topological insulator Bi2Se3 thin films. Fe atoms predominantly and isovalently substitute for two distinct Bi sites at the subsurface with charge neutrality. In the vicinity of Fe substitutions, circular depressions in STM topography and sharp rings in spatially resolved conductance map, whose diameters apparently depend on the tunneling conditions, are observed. We show that the phenomena correlate well with the switching between Fe3+ and Fe2+ charge states due to the gate effect of the tunneling tip, as further evidenced by a multidopant system.

We report on molecular beam epitaxy growth of stoichiometric and superconducting FeSe crystalline thin films on double-layer graphene. Layer-by-layer growth of high-quality films has been achieved in a well-controlled manner by using Se-rich condition, which allow us to investigate the thickness-dependent superconductivity of FeSe. In situ low-temperature scanning tunneling spectra reveal that the local superconducting gap in the quasiparticle density of states is visible down to two triple layers for the minimum measurement temperature of 2.2 K, and that the transition temperature Tc scales inversely with film thickness.

We investigated the electron-pairing mechanism in an iron-based superconductor, iron selenide (FeSe), using scanning tunneling microscopy and spectroscopy. Tunneling conductance spectra of stoichiometric FeSe crystalline films in their superconducting state revealed evidence for a gap function with nodal lines. Electron pairing with twofold symmetry was demonstrated by direct imaging of quasiparticle excitations in the vicinity of magnetic vortex cores, Fe adatoms, and Se vacancies. The twofold pairing symmetry was further supported by the observation of striped electronic nanostructures in the slightly Se-doped samples. The anisotropy can be explained in terms of the orbital-dependent reconstruction of electronic structure in FeSe.

We report on molecular beam epitaxy growth of stoichiometric and superconducting FeSe crystalline thin films on double-layer graphene. Layer-by-layer growth of high-quality films has been achieved in a well-controlled manner by using Se-rich condition, which allow us to investigate the thickness-dependent superconductivity of FeSe. In situ low-temperature scanning tunneling spectra reveal that the local superconducting gap in the quasiparticle density of states is visible down to two triple layers for the minimum measurement temperature of 2.2 K, and that the transition temperature Tc scales inversely with film thickness.

We investigated the electron-pairing mechanism in an iron-based superconductor, iron selenide (FeSe), using scanning tunneling microscopy and spectroscopy. Tunneling conductance spectra of stoichiometric FeSe crystalline films in their superconducting state revealed evidence for a gap function with nodal lines. Electron pairing with twofold symmetry was demonstrated by direct imaging of quasiparticle excitations in the vicinity of magnetic vortex cores, Fe adatoms, and Se vacancies. The twofold pairing symmetry was further supported by the observation of striped electronic nanostructures in the slightly Se-doped samples. The anisotropy can be explained in terms of the orbital-dependent reconstruction of electronic structure in FeSe.

We report on molecular beam epitaxy growth of stoichiometric and superconducting FeSe crystalline thin films on double-layer graphene. Layer-by-layer growth of high-quality films has been achieved in a well-controlled manner by using Se-rich condition, which allow us to investigate the thickness-dependent superconductivity of FeSe. In situ low-temperature scanning tunneling spectra reveal that the local superconducting gap in the quasiparticle density of states is visible down to two triple layers for the minimum measurement temperature of 2.2 K, and that the transition temperature Tc scales inversely with film thickness.

We report on molecular beam epitaxy growth of stoichiometric and superconducting FeSe crystalline thin films on double-layer graphene. Layer-by-layer growth of high-quality films has been achieved in a well-controlled manner by using Se-rich condition, which allow us to investigate the thickness-dependent superconductivity of FeSe. In situ low-temperature scanning tunneling spectra reveal that the local superconducting gap in the quasiparticle density of states is visible down to two triple layers for the minimum measurement temperature of 2.2 K, and that the transition temperature Tc scales inversely with film thickness.

We investigated the electron-pairing mechanism in an iron-based superconductor, iron selenide (FeSe), using scanning tunneling microscopy and spectroscopy. Tunneling conductance spectra of stoichiometric FeSe crystalline films in their superconducting state revealed evidence for a gap function with nodal lines. Electron pairing with twofold symmetry was demonstrated by direct imaging of quasiparticle excitations in the vicinity of magnetic vortex cores, Fe adatoms, and Se vacancies. The twofold pairing symmetry was further supported by the observation of striped electronic nanostructures in the slightly Se-doped samples. The anisotropy can be explained in terms of the orbital-dependent reconstruction of electronic structure in FeSe.

We report on molecular beam epitaxy growth of stoichiometric and superconducting FeSe crystalline thin films on double-layer graphene. Layer-by-layer growth of high-quality films has been achieved in a well-controlled manner by using Se-rich condition, which allow us to investigate the thickness-dependent superconductivity of FeSe. In situ low-temperature scanning tunneling spectra reveal that the local superconducting gap in the quasiparticle density of states is visible down to two triple layers for the minimum measurement temperature of 2.2 K, and that the transition temperature Tc scales inversely with film thickness.

We investigated the electron-pairing mechanism in an iron-based superconductor, iron selenide (FeSe), using scanning tunneling microscopy and spectroscopy. Tunneling conductance spectra of stoichiometric FeSe crystalline films in their superconducting state revealed evidence for a gap function with nodal lines. Electron pairing with twofold symmetry was demonstrated by direct imaging of quasiparticle excitations in the vicinity of magnetic vortex cores, Fe adatoms, and Se vacancies. The twofold pairing symmetry was further supported by the observation of striped electronic nanostructures in the slightly Se-doped samples. The anisotropy can be explained in terms of the orbital-dependent reconstruction of electronic structure in FeSe.

The reductive Bayer digestion by using iron powder as reductant is proposed to convert haematite to magnetite and further to dissociate iron minerals from sodium aluminosilicate hydrate (desilication product, DSP) based on the differences of their surface properties. The results show that the differences of surface properties between magnetite and DSP in zeta potential, wettability and solvation trend facilitate magnetite to agglomerate, increase and thus to dissociate from DSP. The increments of reductant amount and alkali concentration favour the transformation of haematite in digestion with the relative alumina recovery of 98.91%. Processing the resultant red mud can obtain qualified iron concentrate with iron grade of approximate 60% and recovery of about 86% through magnetic separation, resulting in reduction of red mud emission more than 70%. The results show potential to develop a novel technology for processing high iron diasporic bauxite efficiently and provide references for comprehensive utilisation of high iron red mud., The reductive Bayer digestion by using iron powder as reductant is proposed to convert haematite to magnetite and further to dissociate iron minerals from sodium aluminosilicate hydrate (desilication product, DSP) based on the differences of their surface properties. The results show that the differences of surface properties between magnetite and DSP in zeta potential, wettability and solvation trend facilitate magnetite to agglomerate, increase and thus to dissociate from DSP. The increments of reductant amount and alkali concentration favour the transformation of haematite in digestion with the relative alumina recovery of 98.91%. Processing the resultant red mud can obtain qualified iron concentrate with iron grade of approximate 60% and recovery of about 86% through magnetic separation, resulting in reduction of red mud emission more than 70%. The results show potential to develop a novel technology for processing high iron diasporic bauxite efficiently and provide references for comprehensive utilisation of high iron red mud.

Hydrothermal reduction reactions of ferric oxide (Fe2O3) to magnetite (Fe3O4) with iron powder in sodium hydroxide and sodium aluminate solutions under Bayer digestion conditions have been investigated. Thermodynamic calculations show that Fe3O4 is formed by the hydrothermal reduction of ferric oxide with iron at appropriate redox potentials in alkaline solution and the equilibrium concentrations of [Fe(OH)3]- and [Fe(OH)4]- increase with increasing temperature and alkali concentration. Experimental data indicate that the formation ratio of Fe3O4 via the reaction of iron and ferric oxide, or of iron and water, in alkaline solution increases with increase of temperature and alkali concentration. The complex species [Fe(OH)3]- and [Fe(OH)4]- are produced by the dissolution of iron and ferric oxide, respectively, in alkaline solution, and Fe3O4 is subsequently formed by reaction between the two complex species. The hydrothermal reduction of ferric oxide with iron in sodium hydroxide solution is similar to that in sodium aluminate solution. Red muds obtained by the digestion of high-iron diasporic bauxite from Guangxi province, China in the presence of iron powder are found to contain magnetite, whereas no magnetite is detected in the mud without the addition of iron powder., Hydrothermal reduction reactions of ferric oxide (Fe2O3) to magnetite (Fe3O4) with iron powder in sodium hydroxide and sodium aluminate solutions under Bayer digestion conditions have been investigated. Thermodynamic calculations show that Fe3O4 is formed by the hydrothermal reduction of ferric oxide with iron at appropriate redox potentials in alkaline solution and the equilibrium concentrations of [Fe(OH)3]- and [Fe(OH)4]- increase with increasing temperature and alkali concentration. Experimental data indicate that the formation ratio of Fe3O4 via the reaction of iron and ferric oxide, or of iron and water, in alkaline solution increases with increase of temperature and alkali concentration. The complex species [Fe(OH)3]- and [Fe(OH)4]- are produced by the dissolution of iron and ferric oxide, respectively, in alkaline solution, and Fe3O4 is subsequently formed by reaction between the two complex species. The hydrothermal reduction of ferric oxide with iron in sodium hydroxide solution is similar to that in sodium aluminate solution. Red muds obtained by the digestion of high-iron diasporic bauxite from Guangxi province, China in the presence of iron powder are found to contain magnetite, whereas no magnetite is detected in the mud without the addition of iron powder.