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Serious pipe corrosion caused by accumulated $${\text{S}}^{{{2} - }}$$ in Bayer solutions occurs when treating high-sulfur diasporic bauxite by the Bayer process at elevated temperatures. The effects of $${\text{S}}^{{{2} - }}$$ and $${\text{S}}_{{2}} {\text{O}}_{{3}}^{{{2} - }}$$ anions on the corrosion behavior of 16Mn low-alloy steel have been investigated under simulated high-temperature Bayer digestion conditions. The structure of the corrosion layers was analyzed. Results show that $${\text{S}}^{{{2} - }}$$ anions markedly accelerate such corrosion because of the generation of loose FeS-containing corrosion product, whereas $${\text{S}}_{{2}} {\text{O}}_{{3}}^{{{2} - }}$$ anions with concentration > 8.7 g L−1 can remarkably retard the corrosion process by forming a compact magnetite layer with dense and fine particles. Corrosion surface topography analyses support all the experimental corrosion results. Thus, $${\text{S}}_{{2}} {\text{O}}_{{3}}^{{{2} - }}$$ represents an effective corrosion inhibitor for 16Mn low-alloy steel, and $${\text{S}}^{{{2} - }}$$ to $${\text{S}}_{{2}} {\text{O}}_{{3}}^{{{2} - }}$$ transformations may contribute to preventing equipment corrosion when using high-sulfur bauxite in the Bayer process.

Organic radicals, which have unique doublet spin-configuration, provide an alternative method to overcome the efficiency limitation of organic light-emitting diodes (OLEDs) based on conventional fluorescent organic mole-cules. Further, they have made great breakthroughs in deep-red and near-infrared OLEDs. However, it is diffi-cult to extend their fluorescence into a short-wavelength region because of the natural narrow bandgap of the organic radicals. Herein, we significantly expand the scope of luminescent radicals by showing a new platform of carbon-centered radicals derived from N-heterocyclic carbenes that produce blue to green emissions (444–529 nm). Time-dependent density functional theory calculations and experimental investigations disclose that the fluorescence originates from the high-energy excited states to the ground state, demonstrating an anti-Kasha behavior. The present work provides an efficient and modular approach toward a library of carbon-centered radicals that feature anti-Kasha's rule emission, rendering them as potential new emitters in the short-wavelength region.

Five samples of scales collected from various locations in a high-temperature Bayer process plant were characterized via X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, X-ray spectroscopy, and X-ray photoelectron spectroscopy analyses. Then, a method for preventing the formation of scales was proposed. Results showed that the minerals in scales, such as hematite, hydroxyapatite, and sodium aluminate silicate hydrate, are arranged in a layered structure. The difference in arrangement resulted in variations in physical properties, including thickness and hardness. Hematite was facilitated to form thicker layers than magnetite during the scale formation process. Therefore, converting hematite into magnetite by adding a reductant (e.g., glycerol) during Bayer digestion is a feasible strategy for preventing the formation of scales.

Wearable electronics, as essential components of the Internet of Things (IoT), have attracted widespread attention, and the trend is to configure attractive wearable smart microsystems by integrating sensing, powering, and other functions. Herein, we developed an elastic hybrid triboelectric–electromagnetic microenergy harvester (named EHTE) to realize hybrid sensing and microenergy simultaneously. This EHTE is a highly integrated triboelectric nanogenerator (TENG) and electromagnetic nanogenerator (EMG). Based on the triboelectric–electromagnetic hybrid mechanism, an enhanced electrical output of the EHTE was achieved successfully, which demonstrates the feasibility of the EHTE for microelectronics powering. Moreover, with the merits of the EMG, the developed hybrid microenergy harvester integrated both active frequency sensing and passive inductive sensing capabilities. Specifically, the almost linear correlation of the electromagnetic outputs to the frequencies of the external stimulus endowed the proposed EHTE with an outstanding active frequency sensing ability. In addition, due to the unique structural configuration of the EMG (i.e., a conductive permanent magnet (PM), hybrid deformation layer, and flexible printed circuit board (FPCB) coil), an opportunity was provided for the developed EHTE to serve as a passive inductive sensor based on the eddy current effect (i.e., a form of electromagnetic induction). Therefore, the developed EHTE successfully achieved the integration of hybrid sensing (i.e., active frequency sensing and passive inductive sensing) and microenergy (i.e., the combination of electromagnetic effect and triboelectric effect) within a single device, which demonstrates the potential of this newly developed EHTE for wearable electronic applications, especially in applications of compact active microsystems.

Chronic myeloid leukemia (CML) is a myeloproliferative neoplasm. INNO-406 is a novel tyrosine kinase inhibitor (TKI) that possess specific Lyn kinase inhibitory activity with no or limited activity against other sarcoma (Src) family member kinases. The present study aimed to confirm the anti-tumor effect of INNO-406 on CML cells, and elucidate the underlying molecular mechanism. CML cells were treated by INNO-406 at the concentration of 5, 25, 50, 100 μM at the indicated time. Cell proliferation was measured by MTT. Cell apoptosis were detected by Western blot and flow cytometry, respectively. As suggested by the findings, INNO-406 significantly inhibited the proliferation and induced apoptosis of CML cells. In addition, INNO-406 promoted the expression level of PTEN. Rescue experiment revealed that PTEN knockdown reversed the effect of INNO-406 which indicated the correlation between INNO-406 and PTEN. Further study determined that PTEN inhibited the phosphorylation of AKT and 4EBP1 and subsequently altered the expression of apoptotic proteins including bax, cytoplasmic cytochrome c (cyto-c), cleaved caspase3 and bcl-2. In vivo study further confirmed that INNO-406 inhibited the growth of CML cells by targeting PTEN. Based on the above findings, this work extended our understanding of INNO-406 in the therapy of CML and its molecular mechanism.

A novel design incorporating both reductive Bayer digestion and iron recovery into diasporic bauxite processing is proposed to remarkably reduce red mud discharge. This paper presents a comparative study on reductive versus typical Bayer digestion, after which an industrial validation test was carried out. During the test, relative alumina recovery of 98% and a reduction of 10.9% in the amount of red mud generated were achieved by substituting 2 wt.% iron powder for 10 wt.% lime of bauxite in the high-temperature digestion. Meanwhile, ~ 60% of the iron minerals were converted to magnetite by iron powder, meaning that processing the resulting red mud by magnetic separation could obtain iron concentrate with total iron concentration of 55.2% and iron recovery of 60.1%. The overall reduction of red mud discharge reached 50% for a ton of alumina. The proposed prototype is conducive to improve the Bayer process, aiming to achieve cleaner production of commercial alumina.

Three ternary copper(II) complexes [Cu(L1)(phen)] (1), [Cu(L2)(phen)] (2), and [Cu(L3)(phen)]·2H2O (3) (L1 = 4-fluoro-2-(picolinamido)benzoic acid, L2 = 4,5-difluoro-2-(picolinamido)benzoic acid, L3 = 4,5-difluoro-2-((2-hydroxybenzylidene)amino)benzoic acid, phen = 1,10-phenanthroline) have been synthesized and characterized by physicochemical and spectroscopic methods. In addition, X-ray crystallography showed that the Cu atoms in each of the complexes are five-coordinate, adopting distorted square pyramidal or trigonal bipyramidal geometries. The interactions of the complexes with calf-thymus DNA were investigated by UV absorption, fluorescence spectroscopy and viscosity measurements. In addition, the complexes were screened for in vitro cytotoxicity against A549 (human pulmonary carcinoma cells), Jurkat (human T lymphocyte cell line) and HepG-2 (human liver hepatocellular carcinoma cells); these experiments showed that complex 3 exhibited the most effective cytotoxicities (IC50 = 1.224–7.099 µM). Antibacterial studies revealed that complex 3 also exhibited highest activity, consistent with the DNA binding affinities.

In this paper, we present experimental results on the formation of air bubbles in a non-Newtonian liquid. Flow-focusing technology with pressure-driven fluid pumping is used to demonstrate and study the bubble production process. The liquid phase consists of aqueous polyacrylamide at concentrations ranging from 0.01 to 0.10 wt%. Additionally, the solution contains sodium lauryl sulfate, an anionic surfactant, at concentrations ranging from 0.01 to 0.10 wt%. We report on bubble production with pressure ratios (dispersed/continuous phases) ranging from 0.6 to 0.9; the range spans from the minimum ratio required to produce bubbles to the pressure ratio required to produce an air jet. Within this range of pressure ratios, the bubbles lengths are polydisperse, a clear deviation from previous studies involving Newtonian continuous phase fluids. Although the continuous phase contains two additives, we deduce that the polymer is mainly responsible for this change in behavior from Newtonian fluids. The addition of surfactant though provides a means of manipulating this behavior for a certain range of polymer concentrations. We characterize the efficiency of the surfactant by performing a mass transport analysis using Schmidt (Sc), Sherwood (Sh), and Reynolds (Re) numbers. Despite this observation, the average bubble lengths follow trends established for Newtonian fluids.

The solubilities of ethane int-butanol (TBA) and water mixtures have been determined at 10, 15, and 20°C and pressures up to 3.1 MPa. Thermodynamic properties have also been calculated based on the measured solubility data and the hydrophobic interaction for the methane-methane pair interaction in the mixed solvent is discussed.