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Low-grade polymetallic chalcopyrite ore has a high lead and iron content and a low softening point, which is difficult to treat using conventional pyrometallurgical and hydrometallurgical processes. In order to investigate the suitable methodology for efficient utilization, it was pelletized with CaO for oxidation roasting in the present work. By controlling the Po2 and Pso2 in the gas phase, the metal sulfide in the ore was converted into easily soluble metal oxide, the thermal analysis of the roasting process was carried out and the acid leaching of the extracted calcine at atmospheric pressure was investigated. The results show that by pelletizing with CaO and then roasting at 800 ℃ for 1 h, chalcopyrite is converted into CuO, which can be easily dissolved, galena and pyrite are converted into PbO2 and Fe2O3, respectively, and sulfur reacts with CaO and turns into CaSO4, which can fix the sulfur in the calcine. The copper leaching rate of calcine can reach 98.60 wt.% under atmospheric pressure in the H2SO4-H2O system. CaO can increase the softening point of raw materials, improve the roasting effect, promote the phase transformation of chalcopyrite in the oxidation process, and convert sulfur into CaSO4 to fix sulfur, effectively avoiding SO2 pollution to the environment.

OBJECTIVE: Dysregulation of miR-592 has been reported in several tumors. However, its role in acute myeloid leukemia (AML) remains unknown. The present study aimed at investigating the expression pattern and biological function of miR-592 in AML and to elucidate the mechanism involved. PATIENTS AND METHODS: qRT-PCR was used to analyze the expression of miR-592 in bone marrow and serum obtained from AML patients and healthy controls. The associations between serum miR-592 expression and clinical features and prognosis of AML patients were statistically analyzed. Then we detected the effect of miR-592 on proliferation, metastasis and apoptosis by CCK-8 assay, Transwell assays and flow cytometry, respectively. Dual-luciferase reporter assays were performed to validate the regulation of a putative target of miR-592. Rescue experiments were performed to confirm whether ROCK1 was a direct and functional target of miR-592 in AML. RESULTS: We found that the expression level of miR-592 was significantly lower in AML patients and AML cell lines. Low expression of serum miR-592 was associated with advanced French-American-British classification, cytogenetics and poor prognosis. Multivariate analysis confirmed that serum miR-592 expression was an independent prognostic factor for AML patients. Functionally, overexpression of miR- 592 suppressed AML cell growth and metastasis, and promoted apoptosis. Further mechanistic investigation showed ROCK1 was a direct target gene of miR-592. Finally, ROCK1 overexpression rescued the effect of miR-592-mediated AML cell proliferation and metastasis. CONCLUSIONS: These findings suggest that miR-592 acted as a tumor suppressor by targeting ROCK1 and may serve as a potential biomarker in AML. [ABSTRACT FROM AUTHOR]

The endoplasmic reticulum (ER) is crucial for protein quality control, and disruptions in its function can lead to various diseases. ER stress triggers an adaptive response called the unfolded protein response (UPR), which can either restore cellular homeostasis or induce cell death. Melatonin, a safe and multifunctional compound, shows promise in controlling ER stress and could be a valuable therapeutic agent for managing the UPR. By regulating ER and mitochondrial functions, melatonin helps maintain cellular homeostasis via reduction of oxidative stress, inflammation, and apoptosis. Melatonin can directly or indirectly interfere with ER-associated sensors and downstream targets of the UPR, impacting cell death, autophagy, inflammation, molecular repair, among others. Crucially, this review explores the mechanistic role of melatonin on ER stress in various diseases including liver damage, neurodegeneration, reproductive disorders, pulmonary disease, cardiomyopathy, insulin resistance, renal dysfunction, and cancer. Interestingly, while it alleviates the burden of ER stress in most pathological contexts, it can paradoxically stimulate ER stress in cancer cells, highlighting its intricate involvement in cellular homeostasis. With numerous successful studies using in vivo and in vitro models, the continuation of clinical trials is imperative to fully explore melatonin's therapeutic potential in these conditions., (© 2024 Wiley Periodicals LLC.)

The rapid advancement of triboelectric nanogenerators (TENGs) has introduced a transformative approach to energy harvesting and self-powered sensing in recent years. Nonetheless, the untapped potential of TENGs in practical scenarios necessitates multiple strategies like material selections and structure designs to enhance their output performance. Given the various superior properties, MXenes, a kind of novel 2D materials, have demonstrated great promise in enhancing TENG functionality. Here, this review comprehensively delineates the advantages of incorporating MXenes into TENGs, majoring in six pivotal aspects. First, an overview of TENGs is provided, stating their theoretical foundations, working modes, material considerations, and prevailing challenges. Additionally, the structural characteristics, fabrication methodologies, and family of MXenes, charting their developmental trajectory are highlighted. The selection of MXenes as various functional layers (negative and positive triboelectric layer, electrode layer) while designing TENGs is briefed. Furthermore, the distinctive advantages of MXene-based TENGs and their applications are emphasized. Last, the existing challenges are highlighted, and the future developing directions of MXene-based TENGs are forecasted., (© 2024 Wiley‐VCH GmbH.)

Halide perovskite, renowned for its multifunctional properties, shows considerable promise for realizing self-charging power systems. In this study, a lead-free methylammonium bismuth iodide (MA 3 Bi 2 I 9 ) perovskite is used to create a self-charging power unit (SPU). This involves constructing a hybrid piezoelectric-triboelectric nanogenerator (Hybrid-TENG) and utilizing MA 3 Bi 2 I 9 for energy storage as an anode in a lithium-ion battery (LIB). Initially, MA 3 Bi 2 I 9 nanorods are synthesized and composited with a polystyrene-block-poly(ethylene-ran-butylene)-block-polystyrene polymer. The dielectric and mechanical properties of composite films having perovskite loading content are investigated. The optimized Hybrid-TENG exhibits superior performance, generating a voltage of 537 V, current density of 13.2 µA cm - 2 , and maximum power density of 3.04 mW cm -2 , which can be attributed to the high piezoelectric coefficient of MA 3 Bi 2 I 9 nanorods (≈20.6 pm V -1 ). A MA 3 Bi 2 I 9 thin film, serving as an electrode in LIB, demonstrates a high specific capacity of 2378.9 mAh cm -3 mAh g   mAh g -1 ) with a capacity retention of ≈87.5% over 100 cycles, underscoring its stable performance. Furthermore, a Hybrid-TENG is employed to charge the MA 3 Bi 2 I 9 -based LIB, thus realizing an SPU for driving portable electronics. This study highlights the promising potential of perovskites for developing efficient nanogenerators and LIBs, paving the way for sustainable energy solutions in small-scale electronics., (© 2024 Wiley‐VCH GmbH.)

The precipitation kinetics of γ′-Ni3(Al, Ta) phase and creep properties of Ni-15Al-xTa at.% superalloys are investigated by the crystal plasticity phase-field simulation. The results show that the high Ta content brings a lower creep strain for the deceleration and steady creep stage, while the creep lifetime is shorter. The large external strain intensifies the creep damage and shortens the creep life of Ni-15Al-3Ta at.% superalloy. The kinetics evolution and elements distribution are revealed in the quaternary Ni-10Al-8.5Cr-xTa (x = 1.5 at.%, 2.0 at.%, 2.5 at.%) superalloys by the multi-component phase-field simulation. The anti-phase boundary (APB) changes the coarsening mechanism of γ′ phase, and Ta promotes the precipitation of γ′ phase with an increasing volume fraction and particle number. The composition difference between γ′ and γ phases increases with the rising of Ta content, the strong partitioning of Ta to γ′ phase strengthens the partitioning of Ni and Cr to γ matrix, and Ta shows a superiority than Al in the lattice site occupation of L12-Ni3(Al, X) phases. As an important γ′ phase forming element, the optimization of Ta content is essential for improving the mechanical properties of Ni-based superalloys. [ABSTRACT FROM AUTHOR]

Pseudobinary Pr[sub 1-x]Tb[sub x](Fe[sub 0.6]Co[sub 0.4])[sub 2] (0≤x≤0.4) cubic Laves single phases have been synthesized by melt spinning and subsequent annealing. Their structure, magnetic properties and stability have been investigated. The composition, at which the anisotropy of Pr[sub 1-x]Tb[sub x](Fe[sub 0.6]Co[sub 0.4])[sub 2] is compensated, is close to x=0.1. The spontaneous magnetostrictions λ[sub 111] of Pr[sub 0.9]Tb[sub 0.1](Fe[sub 0.6]Co[sub 0.4])[sub 2] and Pr[sub 0.8]Tb[sub 0.2](Fe[sub 0.6]Co[sub 0.4])[sub 2] are larger than 1500×10[sup -6] and 1900×10[sup -6], respectively. Pr[sub 1-x]Tb[sub x](Fe[sub 0.6]Co[sub 0.4])[sub 2] (0.1≤x≤0.4) ribbon-based materials with 3% epoxy resin combine high magnetostriction with significant magnetic coercivity. Pr[sub 0.9]Tb[sub 0.1](Fe[sub 0.6]Co[sub 0.4])[sub 2] is a promising magnetostrictive material. © 2002 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The discovery of non-precious catalysts for replacing the precious metal of ruthenium in the oxygen evolution reaction (OER) represents a key step in reducing the cost of green hydrogen production. The 2D d-MHOFs, a new 2D materials with controllable oxygen vacancies formed by controlling the degree of coordination bridging between metal hydroxyl oxide and BDC ligands are synthesized at room temperature, exhibit excellent OER properties with low overpotentials of 207  mV at 10 mA cm -2 . High-resolution transmission electron microscopy images and density functional theory calculations demonstrate that the introduction of oxygen vacancy sites leads to a lattice distortion and charge redistribution in the catalysts, enhancing the OER activity of 2D d-MHOFs comprehensively. Synchrotron radiation and in situ Raman/Fourier transform infrared spectroscopy indicate that part of oxygen defect sites on the surface of 2D d-MHOFs are prone to transition to highly active metal hydroxyl oxides during the OER process. This work provides a mild strategy for scalable preparation of 2D d-MHOFs nanosheets with controllable oxygen defects, reveals the relationship between oxygen vacancies and OER performance, and offers a profound insight into the basic process of structural transformation in the OER process., (© 2024 Wiley‐VCH GmbH.)