Outstanding Performance of Magnetically Separable Sulfureted MoO3/Fe-Ti Spinel for Gaseous Hg0 Recovery from Smelting Flue Gas: Mechanism and Adsorption Kinetics.

To replace the hazardous and complicated Boliden-Norzink technology, the technology of Hg0 recovery from smelting flue gas by a magnetic and reproducible sulfureted MoO3/Fe-Ti spinel was employed to keep the produced H2SO4 free of Hg. The sulfureted MoO3/Fe-Ti spinel showed excellent performance in capturing gaseous Hg0, with an average adsorption rate of 93.3 µg g-1 min-1 and an adsorption capacity of 66.3 mg g-1 at 60 °C, which were much better than those of most of the other reported sorbents. Meanwhile, the sulfureted MoO3/Fe-Ti spinel exhibited excellent superparamagnetism and magnetization of 19.9 emu g-1, which ensured that it could easily be magnetically separated without a specialized precipitator or the molding of pulverous sorbents to monolithic sorbents. To investigate the promotion mechanism of MoO3 loading on Hg0 adsorption onto the sulfureted Fe-Ti spinel, the Hg0 adsorption kinetic parameters of the sulfureted MoO3/Fe-Ti spinel and sulfureted Fe-Ti spinel, resulting from the fitting of the adsorption breakthrough curves based on the kinetic model, were compared. The promotion of MoO3 loading was attributed to the remarkable increase in the adsorption sites on the sulfureted Fe-Ti spinel for Hg0 physical adsorption, which was mainly related to the formation of the MoS3 layer.

Novel Synergistic Effect of Fe and Mo in FeMoSx/TiO2 for Recovering High Concentrations of Gaseous Hg0 from Smelting Flue Gas: Reaction Mechanism and Kinetics.

There is a high demand for developing a more effective and environment-friendly technology to substitute the complicated and hazardous Boliden-Norzink technology for recovering gaseous Hg0 from smelting flue gas. In this work, a low-cost and reproducible sorbent (FeMoSx/TiO2) was developed to recover gaseous Hg0 from smelting flue gas. FeMoSx/TiO2 exhibited a superior ability for capturing high concentrations of Hg0, with an adsorption rate of 72.2 µg g-1 min-1 and a capacity of 41.8 mg g-1 at 60 °C. These were generally larger than the sums of those of FeSx/TiO2 and MoSx/TiO2. The kinetic model of Hg0 adsorption by FeSx/TiO2, MoSx/TiO2, and FeMoSx/TiO2 were constructed according to the adsorption mechanism. Then, the structure-activity relationship of FeMoSx/TiO2 for Hg0 capture was determined by comparing the kinetic parameters. The intrinsic adsorption of Hg0 by MoSx/TiO2 (i.e., physically adsorbed Hg0 was oxidized by MoS3 to HgS) was inhibited marginally after FeSx was incorporated. However, another Hg0 adsorption route (i.e., physically adsorbed Hg0 was oxidized by FeS2 to HgS) appeared on FeMoSx/TiO2. Its rate was significantly higher than that of FeSx/TiO2. Thus, a novel synergistic effect of Fe and Mo in FeMoSx/TiO2 for Hg0 capture was observed.

Significant Enhancement of Gaseous Elemental Mercury Recovery from Coal-Fired Flue Gas by Phosphomolybdic Acid Grafting on Sulfurated γ-Fe2O3: Performance and Mechanism.

The existing technologies to control Hg emissions from coal-fired power plants can be improved to achieve the centralized control of Hg0 emissions, which continue to pose a risk of Hg exposure to human populations. In this work, MoSx@γ-Fe2O3, formed by the sulfuration of phosphomolybdic acid (HPMo)-grafted γ-Fe2O3, was developed as a magnetic and regenerable sorbent to recover gaseous Hg0 from coal-fired flue gas as a cobenefit to the use of wet electrostatic precipitators. The thermal stability of γ-Fe2O3 was notably enhanced by HPMo grafting; thus, the magnetization of MoSx@γ-Fe2O3 hardly decreased during the application. The kinetic analysis indicates that the chemical adsorption of gaseous Hg0 was mainly dependent on the amounts of surface S22- and surface adsorption sites. Although the amount of S22- on sulfurated γ-Fe2O3 decreased after HPMo grafting, the amount of surface adsorption sites significantly increased due to the formation of a layered MoSx structure on the surface. Therefore, the ability of sulfurated γ-Fe2O3 to capture Hg0 was improved considerably after HPMo grafting. Furthermore, low concentrations of gaseous Hg0 in coal-fired flue gas can be gradually enriched by at least 1000 times by MoSx@γ-Fe2O3, which facilitates the recovery and centralized control of gaseous Hg0 in flue gas.

Outstanding Performance of Recyclable Amorphous MoS3 Supported on TiO2 for Capturing High Concentrations of Gaseous Elemental Mercury: Mechanism, Kinetics, and Application.

Hg0 capture by sorbents was a promising technology to control Hg0 emission from coal-fired power plants and smelters. However, the design of a high performance sorbent and the predicting of the extent of Hg0 adsorption were both extremely limited due to the lack of adsorption kinetics and structure-activity relationship. In this work, the adsorption kinetics of gaseous Hg0 onto MoS3/TiO2 was investigated and kinetic parameters were obtained by fitting breakthrough curves. According to the kinetic parameters, the removal efficiency, the adsorption rate and the capacity for Hg0 capture were accurately predicted. Meanwhile, the structure-activity relationship of metal sulfides for gaseous Hg0 adsorption was built. The chemical adsorption rate of gaseous Hg0 was found to mainly depend on the amount of surface adsorption sites available for the physical adsorption of Hg0, the amount of surface S22- available for Hg0 oxidation and gaseous Hg0 concentration. As MoS3/TiO2 showed a superior performance for capturing high concentrations of Hg0 due to the large number of surface adsorption sites for the physical adsorption of gaseous Hg0, it has promising applications in recovering Hg0 from smelting flue gas.

Role of purinergic receptors in cardiac sympathetic nerve injury in diabetes mellitus.

Diabetic cardiac autonomic neuropathy is a common and serious chronic complication of diabetes, which can lead to sympathetic and parasympathetic nerve imbalance and a relative excitation of the sympathetic nerve. Purinergic receptors play a crucial role in this process. Diabetic cardiac sympathetic nerve injury affects the expression of purinergic receptors, and activated purinergic receptors affect the phosphorylation of different signaling pathways and the regulation of inflammatory processes. This paper introduces the abnormal changes of sympathetic nerve in diabetes mellitus and summarizes the recently published studies on the role of several purinergic receptor subtypes in diabetic cardiac sympathetic nerve injury. These studies suggest that purinergic receptors as novel drug targets are of great significance for the treatment of diabetic autonomic neuropathy. This article is part of the Special Issue on "Purinergic Signaling: 50 years".

Revisiting the intersection of microglial activation and neuroinflammation in Alzheimer's disease from the perspective of ferroptosis.

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by chronic neuroinflammation with amyloid beta-protein deposition and hyperphosphorylated tau protein. The typical clinical manifestation of AD is progressive memory impairment, and AD is considered a multifactorial disease with various etiologies (genetic factors, aging, lifestyle, etc.) and complicated pathophysiological processes. Previous research identified that neuroinflammation and typical microglial activation are significant mechanisms underlying AD, resulting in dysfunction of the nervous system and progression of the disease. Ferroptosis is a novel modality involved in this process. As an iron-dependent form of cell death, ferroptosis, characterized by iron accumulation, lipid peroxidation, and irreversible plasma membrane disruption, promotes AD by accelerating neuronal dysfunction and abnormal microglial activation. In this case, disturbances in brain iron homeostasis and neuronal ferroptosis aggravate neuroinflammation and lead to the abnormal activation of microglia. Abnormally activated microglia release various pro-inflammatory factors that aggravate the dysregulation of iron homeostasis and neuroinflammation, forming a vicious cycle. In this review, we first introduce ferroptosis, microglia, AD, and their relationship. Second, we discuss the nonnegligible role of ferroptosis in the abnormal microglial activation involved in the chronic neuroinflammation of AD to provide new ideas for the identification of potential therapeutic targets for AD.

Schisandrin B Alleviates Diabetic Cardiac Autonomic neuropathy Induced by P2X7 Receptor in Superior Cervical Ganglion via NLRP3.

Diabetic cardiovascular autonomic neuropathy (DCAN) is a common complication of diabetes mellitus which brings about high mortality, high morbidity, and large economic burden to the society. Compensatory tachycardia after myocardial ischemia caused by DCAN can increase myocardial injury and result in more damage to the cardiac function. The inflammation induced by hyperglycemia can increase P2X7 receptor expression in the superior cervical ganglion (SCG), resulting in nerve damage. It is proved that inhibiting the expression of P2X7 receptor at the superior cervical ganglion can ameliorate the nociceptive signaling dysregulation induced by DCAN. However, the effective drug used for decreasing P2X7 receptor expression has not been found. Schisandrin B is a traditional Chinese medicine, which has anti-inflammatory and antioxidant effects. Whether Schisandrin B can decrease the expression of P2X7 receptor in diabetic rats to protect the cardiovascular system was investigated in this study. After diabetic model rats were made, Schisandrin B and shRNA of P2X7 receptor were given to different groups to verify the impact of Schisandrin B on the expression of P2X7 receptor. Pathological blood pressure, heart rate, heart rate variability, and sympathetic nerve discharge were ameliorated after administration of Schisandrin B. Moreover, the upregulated protein level of P2X7 receptor, NLRP3 inflammasomes, and interleukin-1ß in diabetic rats were decreased after treatment, which indicates that Schisandrin B can alleviate the chronic inflammation caused by diabetes and decrease the expression levels of P2X7 via NLRP3. These findings suggest that Schisandrin B can be a potential therapeutical agent for DCAN.

Aerobic granular sludge formation and stability in enhanced biological phosphorus removal system under antibiotics pressure: Performance, granulation mechanism, and microbial successions.

Wastewater containing antibiotics can pose a significant threat to biological wastewater treatment processes. This study investigated the establishment and stable operation of enhanced biological phosphorus removal (EBPR) by aerobic granular sludge (AGS) under mixed stress conditions induced by tetracycline (TC), sulfamethoxazole (SMX), ofloxacin (OFL), and roxithromycin (ROX). The results show that the AGS system was efficient in removing TP (98.0%), COD (96.1%), and NH4+-N (99.6%). The average removal efficiencies of the four antibiotics were 79.17% (TC), 70.86% (SMX), 25.73% (OFL), and 88.93% (ROX), respectively. The microorganisms in the AGS system secreted more polysaccharides, which contributed to the reactor's tolerance to antibiotics and facilitated granulation by enhancing the production of protein, particularly loosely bound protein. Illumina MiSeq sequencing revealed that putative phosphate accumulating organisms (PAOs)-related genera (Pseudomonas and Flavobacterium) were enormously beneficial to the mature AGS for TP removal. Based on the analysis of extracellular polymeric substances, extended Derjaguin-Landau-Verwey-Overbeek (XDLVO) theory, and microbial community, a three-stage granulation mechanism was proposed including adaption to the stress environment, formation of early aggregates and maturation of PAOs enriched microbial granules. Overall, the study demonstrated the stability of EBPR-AGS under mixed antibiotics pressure, providing insight into the granulation mechanism and the potential use of AGS for wastewater treatment containing antibiotics.

Outstanding performance of sulfurated titanomaghemite (Fe2TiO5) for hexavalent chromium removal: Sulfuration promotion mechanism and its application in chromium resource recovery.

A lot of magnetic sorbents have been developed to meet the current demand for removing Cr (VI) from wastewater. However, the application of magnetic sorbents remains restricted by the unsatisfactory Cr (VI) removal efficiency, sorbent regeneration, and safe disposition of adsorbed Cr species. In this study, magnetic titanomaghemite (Fe2TiO5) was sulfurated with gaseous H2S to improve its Cr (VI) removal efficiency. Sulfuration significantly improved the Cr (VI) removal efficiency of Fe2TiO5 from 3%-14% to 27%-82% at pH 4-10 due to drastically increased the electrostatic adsorption of Cr (VI) and heterogeneous reduction of adsorbed Cr (VI) to Cr (III). Furthermore, the sulfurated Fe2TiO5 recovered using magnetic separation can be regenerated by re-sulfuration without degrading the Cr (VI) removal efficiency, therefore, sulfurated Fe2TiO5 can be recycled for Cr (VI) removal after the regeneration. Moreover, Cr (VI) in aqueous solution can be enriched on sulfurated Fe2TiO5 after multiple adsorptions in the form of Cr2O3 in a content of more than 30% what can be considered as a source of chrome ore. Therefore, sulfurated Fe2TiO5 may be a promising, low-cost, and environment-friendly sorbent for Cr recovery as a co-benefit of Cr (VI) removal from wastewater.

Beneficial Effects of lncRNA-UC.360+ shRNA on Diabetic Cardiac Sympathetic Damage via NLRP3 Inflammasome-Induced Pyroptosis in Stellate Ganglion.

Hyperglycemia is one of the common symptoms of diabetes, and it produces excessive reactive oxygen species (ROS). This study investigated whether the long noncoding RNA (lncRNA) UC.360+ is involved in diabetic cardiac autonomic neuropathy (DCAN) mediated by NLRP3 inflammasome-induced pyroptosis in the stellate ganglion (SG). Using a rat type 2 diabetes model, we found that lncRNA UC.360+ short hairpin RNA (shRNA) ameliorated the dyslipidaemia of type 2 diabetic rats and reduced serum adrenaline and ROS production in SG under hyperglycemia. In addition, UC.360+ shRNA also reduced the expression of nuclear factor kappa-B (NF-κB), NLRP3, ASC, caspase-1, interleukin-1ß (IL-1ß), and IL-18 in the SG of diabetic rats and inhibited the phosphorylation of p38 mitogen-activated protein kinase (p38 MAPK). Therefore, lncRNA-UC.360+ shRNA may modulate the NLRP3 inflammasome/inflammatory pathway in the SG, which in turn alleviates diabetic heart sympathetic nerve damage.

Naringin Relieves Diabetic Cardiac Autonomic Neuropathy Mediated by P2Y14 Receptor in Superior Cervical Ganglion.

Diabetes mellitus (DM), an emerging chronic epidemic, contributes to mortality and morbidity around the world. Diabetic cardiac autonomic neuropathy (DCAN) is one of the most common complications associated with DM. Previous studies have shown that satellite glial cells (SGCs) in the superior cervical ganglia (SCG) play an indispensable role in DCAN progression. In addition, it has been shown that purinergic neurotransmitters, as well as metabotropic GPCRs, are involved in the pathophysiological process of DCAN. Furthermore, one traditional Chinese medicine, naringin may potently alleviate the effects of DCAN. Ferroptosis may be involved in DCAN progression. However, the role of naringin in DCAN as well as its detailed mechanism requires further investigation. In this research, we attempted to identify the effect and relevant mechanism of naringin in DCAN mitigation. We observed that compared with those of normal subjects, there were significantly elevated expression levels of P2Y14 and IL-1ß in diabetic rats, both of which were remarkably diminished by treatment with either P2Y14 shRNA or naringin. In addition, abnormalities in blood pressure (BP), heart rate (HR), heart rate variability (HRV), sympathetic nerve discharge (SND), and cardiac structure in the diabetic model can also be partially returned to normal through the use of those treatments. Furthermore, a reduced expression of NRF2 and GPX4, as well as an elevated level of ROS, were detected in diabetic cases, which can also be improved with those treatments. Our results showed that naringin can effectively relieve DCAN mediated by the P2Y14 receptor of SGCs in the SCG. Moreover, the NRF2/GPX4 pathway involved in ferroptosis may become one of the principal mechanisms participating in DCAN progression, which can be modulated by P2Y14-targeted naringin and thus relieve DCAN. Hopefully, our research can supply one novel therapeutic target and provide a brilliant perspective for the treatment of DCAN.

LncRNA-UC.25 + shRNA Alleviates P2Y14 Receptor-Mediated Diabetic Neuropathic Pain via STAT1.

Diabetic neuropathic pain (DNP) is a common complication of diabetes, and its complicated pathogenesis, as well as clinical manifestations, has brought great trouble to clinical treatment. The spinal cord is an important part of regulating the occurrence and development of DNP. Spinal microglia can regulate the activity of spinal cord neurons and have a regulatory effect on chronic pain. P2Y12 receptor is involved in DNP. P2Y14 and P2Y12 receptors belong to the Gi subtype of P2Y receptors, but there is no report that the P2Y14 receptor is involved in DNP. Closely related to many human diseases, the dysregulation of long noncoding RNA (lncRNA) has the effect of promoting or inhibiting the occurrence and development of diseases. The aim of this research is to investigate the function of the spinal cord P2Y14 receptor in type 2 DNP and to understand the function as well as the possible mechanism of lncRNA-UC.25 + (UC.25 +) in rat spinal cord P2Y14 receptor-mediated DNP. Our results showed that P2Y14 shRNA can reduce the expression of P2Y14 in DNP rats, thereby restraining the activation of microglia, decreasing the expression of inflammatory factors and the level of p38 mitogen-activated protein kinase (p38 MAPK) phosphorylation. At the same time, UC.25 + shRNA can downregulate the expression of the P2Y14 receptor, reduce the release of inflammatory factors, and diminish the p38 MAPK phosphorylation, indicating that UC.25 + can alleviate spinal cord P2Y14 receptor-mediated DNP. The RNA immunoprecipitation result showed that UC.25 + enriched signal transducers and activators of transcription1 (STAT1) and positively regulated its expression. The chromatin immunoprecipitation result indicated that STAT1 combined with the promoter region of the P2Y14 receptor and positively regulated the expression of the P2Y14 receptor. Therefore, we infer that UC.25 + may alleviate DNP in rats by regulating the expression of the P2Y14 receptor in spinal microglia via STAT1.

Outstanding performance of ZnS/TiO2 for the urgent disposal of liquid mercury leakage indoors: Novel support effect, reaction mechanism and kinetics.

Effectively weakening the bond strength of Zn-S in S-Zn-S on ZnS is of great significance to the improvement of its performance for the urgent disposal of liquid Hg0 leakage indoors. In this work, ZnS was loaded on three common supports (i.e., TiO2, SiO2, and Al2O3) to further improve its performance for capturing high concentrations of Hg0 indoors. After being loaded on TiO2, the S-Zn-O bond was present on ZnS, and the bond strength of Zn-S in S-Zn-O was significantly weaker than that in S-Zn-S because Zn2+ preferred to O2- than S2-. Hence, physically adsorbed Hg0 was much easier to bond with S in S-Zn-O than that in S-Zn-S to form HgS. Therefore, TiO2 showed a novel support effect on ZnS for Hg0 capture, and the Hg0 capture performance of ZnS/TiO2 was greatly better than those of ZnS, ZnS/SiO2, and ZnS/Al2O3. Moreover, the promotion mechanism of ZnO loading on Hg0 adsorption onto TiO2-S was discovered after comparing the Hg0 adsorption kinetic parameters of TiO2-S and ZnS/TiO2. The promotion of ZnO loading was primarily related to the notable increase in the content of S2- that can bond with physically adsorbed Hg0, which predominantly resulted from the strong interaction of ZnO/TiO2 with H2S.

Remarkable differences between copper-based sulfides and iron-based sulfides for the adsorption of high concentrations of gaseous elemental mercury: Mechanisms, kinetics, and significance.

Copper sulfides (CuSx) and iron sulfides (FeSx) have been developed to capture gaseous elemental mercury (Hg0) originating from the smelting flue gas. However, these compounds exhibit different Hg0 adsorption characteristics and Hg species adsorbed on CuSx can be spontaneously released as gaseous Hg0. Following these findings, the adsorption/desorption kinetics of Hg0 onto and from FeSx and CuSx were determined. After comparing the kinetic parameters, the mechanisms behind some of the remarkable differences between FeSx and CuSx with respect to Hg0 adsorption were discovered. The Cu-S bond in CuSx was not completely broken during Hg0 oxidation, but the SS bond in FeSx was. Hence, the activation energy for the oxidation of Hg0 physically adsorbed on CuSx was much lower than that for FeSx, resulting in a much higher efficiency of CuSx to oxidize Hg0 than FeSx. However, the bond strength of Hg-S for HgS on CuSx was weaker due to the sharing of S2- in HgS with Cu+, resulting in a decrease in the thermal stability of HgS on CuSx. Therefore, HgS adsorbed on Cu-based sulfides was metastable, and could be spontaneously decomposed to release moderate concentrations of gaseous Hg0, which was not preferable for capturing high concentrations of Hg0.

Remarkable improvement of Ti incorporation on Hg0 capture from smelting flue gas by sulfurated γ-Fe2O3: Performance and mechanism.

Except for the dangerous Boliden-Norzink technology, recovering gaseous Hg0 as liquid Hg0 using recyclable sorbents was an achievable method to control Hg0 emissions from smelting flue gas. In this study, Ti was incorporated into sulfurated γ-Fe2O3 to improve its performance for capturing Hg0 from smelting flue gas, and the mechanism of Ti incorporation on Hg0 adsorption onto sulfurated γ-Fe2O3 was investigated by comparing the kinetic parameters. The kinetic analysis showed that the Hg0 adsorption rate primarily depended on the amounts of surface adsorption sites for the physical adsorption of Hg0 and surface S22- for Hg0 oxidation. Since the amounts of both adsorption sites and S22- on sulfurated γ-Fe2O3 increased remarkably after Ti incorporation, Hg0 adsorption onto sulfurated γ-Fe2O3 was notably improved by 190-350%. The capacity of sulfurated Fe-Ti spinel for Hg0 capture could reach 48.6 mg g-1 and its average adsorption rate could reach 43.3 µg g-1 min-1 in 3 h. Meanwhile, the used sulfurated Fe-Ti spinel could be easily regenerated without any apparent degradation. Thus, sulfurated Fe-Ti spinel offered a significant advantage in recovering Hg0 from smelting flue gas.