Oxide Systems Research Articles

Selective micropollutants removal in wastewaters by non-radical activation of peroxymonosulfate: Multiparameter analysis of electron-donating capacity

Understanding the electron-donating capacity (EDC) of pollutants in selective advanced oxidation systems is crucial for efficient wastewater decontamination. A novel catalyst, composed of a zeolitic imidazolate framework (ZIF)-derived Co3O4 and carbon nanotubes (CNTs), was synthesized for peroxymonosulfate (PMS) activation. This multiphase PMS activation system efficiently degraded organic pollutants (OPs) with high EDC, indicated by their Hammett constant (σρ) and energy of the highest occupied molecular orbital (EHOMO), achieving a mineralization rate of 83.63 % within 15 min. Singlet oxygen and Co(IV) were identified as the primary reactive species in wastewater decontamination. The electron transfer pathway played a pivotal role in converting Co(II) to Co(IV) and oxidizing OPs. Moreover, the multiphase PMS activation system maintained high activity and selectivity in practical hospital wastewater decontamination. This study offers insights into selective decontamination for complex wastewaters, leveraging the EDC of OPs and the advantages of non-radical-dominated advanced oxidation processes.

Non-radical oxidation driven by iron-based materials without energy assistance in wastewater treatment.

Chemical oxidation is extensively utilized to mitigate the impact of organic pollutants in wastewater. The non-radical oxidation driven by iron-based materials is noted for its environmental friendliness and resistance to wastewater matrix, and it is a promising approach for practical wastewater treatment. However, the complexity of heterogeneous systems and the diversity of evolutionary pathways make the mechanisms of non-radical oxidation driven by iron-based materials elusive. This work provides a systematic review of various non-radical oxidation systems driven by iron-based materials, including singlet oxygen (1O2), reactive iron species (RFeS), and interfacial electron transfer. The unique mechanisms by which iron-based materials activate different oxidants (ozone, hydrogen peroxide, persulfate, periodate, and peracetic acid) to produce non-radical oxidation are described. The roles of active sites and the unique structures of iron-based materials in facilitating non-radical oxidation are discussed. Commonly employed identification methods in wastewater treatment are compared, such as quenching, chemical probes, spectroscopy, mass spectrometry, and electrochemical testing. According to the process of iron-based materials driving non-radical oxidation to remove organic pollutants, the driving factors at different stages are summarized. Finally, challenges and countermeasures are proposed in terms of mechanism exploration, detection methods and practical applications of non-radical oxidation driven by iron-based materials. This work provides valuable insights for understanding and developing non-radical oxidation systems.

Experimental Verification of Inter Relation between Fowler–Nordheim and Millikan–Lauritsen Plot in Chemically Synthesized Zinc Oxide System

AbstractCold cathode emission or cold field emission (CFE) is a purely quantum mechanical phenomenon and a phenomenon of wonder. The exact science behind the observed current (I)–voltage (V) is yet to be pin pointed. For instance, a good cold emitter is very reasonably supposed to have low work function and good conductivity whereas a carbon allotropes like diamonds have just the reverse in both the cases, i.e., it is insulating in nature having very wide band gap as well as high work function yet it is considered to be an efficient field emitter. Since early of 20th century, till its middle a number of groups have suggested different equations or relations that can adequately describe the experimental CFE I–V characteristics adequately. Although they all fundamentally follow an exponential law, but so far, the relation suggests by Fowler and Nordheim (F–N) is the most accepted one. However, there is another relationship suggested by Millikan and Lauritsen (M–L) which is in spite of being reasonable not so common now a day to use. This work revisits different popular approaches for analyzing cold emission data. With this aim, the experimental CFE data obtained for chemically synthesized zinc oxide nanorods are chosen. The proper phase formation of ZnO is confirmed by XRD study whereas FESEM shows the rod like morphology. EDX confirms the proper stoichiometric ratio for the sample. After detail analysis it is confirmed that the theoretically proposed relation between F–N and M–L experimentally holds good as well and thus it would not be wrong to analyze the CFE data by simple M–L theory.

Diamagnetic to Ferromagnetic Like Transition of Non-Stoichiometry Barium Titanate (BaTiO3-x) Prepared by Sol-gel Method

The oxygen vacancy properties are significant, creating ferromagnetic properties of material in metal oxide systems like dilute magnetic semiconductors. An aqueous sol-gel method has been used in the present study to synthesize non-stoichiometry BaTiO3-x polycrystalline. In an attempt of examining the oxygen deficiency consequences on the magnetic properties, the gel samples were sintered (1000◦C) at various times (6, 12, 18, and 24 hours) under a vacuum environment. This study employs an X-ray diffraction apparatus in terms of characterizing segments and structures of the samples. It also investigates morphology and element distribution on the surface of the samples exploiting an Electron microscope where Energy dispersive spectroscopy is supplied. For the purpose of characterizing the magnetic properties of the samples, it applies vibrating sample magnetometers. The chemical state of the element and its corresponding bond to other elements was identified using X-ray photoelectron spectroscopy. Single-phase compounds were observed. The crystal system is tetragonal, but the crystal parameters are different. Increase sintering time leads to increase crystallite size and decrease in micro strain. Moreover, sintering in a vacuum environment results in oxygen deficiency and leads to the atomic ratio of Ba/Ti change as the sintering time increases. The Ba/Ti ratio change affects the transformation from diamagnetic to ferromagnetic-like. The elements (Ba, Ti and O) chemical state is shown and its bonding to the corresponding element along with the X-ray photoelectron spectroscopy pattern of the BTX2 sample. The element of oxygen binds to Ti and Ba while Ba element exists in two chemical states.

A tandem dual-pathway non-radical water purification simultaneously induced by single-molecule peroxymonosulfate with a catalyst of coexisting Cu single atoms and Fe3C nanoparticles

The non-radical pathways of persulfate (PMS/PS)-based heterogeneous advanced oxidation processes offer effective means for treating complex water matrices. However, the large-scale application is hindered by the increased input costs and substantial accumulation of SO42–. Therefore, it is crucial to develop novel pathways for efficient PMS/PS activation. Here, we construct a CuSA/Fe3C-NC catalyst with Cu single atoms (SAs) and Fe3C nanoparticles (NPs) co-anchored on a carbon support. The improved d-band centers of Cu and Fe elements optimize the PMS adsorption and activation. Unlike previous studies, the electron acceptor PMS in electron transfer process is not be converted to SO42– but rather to singlet oxygen (1O2) via superoxide radicals (O2•–). A tandem dual-pathway non-radical oxidation system induced by a single-molecule PMS leads to higher PMS utilization. Under extremely low catalyst and PMS dosage conditions (catalyst dosage = 0.04 g/L, PMS dosage = 0.2 mmol/L), CuSA/Fe3C-NC + PMS system can rapidly remove bisphenol A within 30 min and achieve a mineralization rate of 85 %. This work provides strong support for the rational design of catalyst structures to achieve low-input and high-efficiency water purification processes.

Novel High-Entropy oxide Achieves high capacity and stability as an anode for Lithium-Ion batteries

High-entropy oxides possess high theoretical capacity, stable chemical structure, making them highly promising as battery electrode materials. The limited successful synthesis of high-entropy oxide systems has hindered their further development. This study synthesized a six-component high-entropy spinel oxide (FeCoMgCrLiZn)3O4 for the first time and evaluated its electrochemical performance as an anode for lithium-ion batteries. The data show that this single-phase oxide exhibits a high reversible capacity (stabilizing at 800 mAh/g after 300 cycles at 200 mA/g), good cycling stability (800 stable cycles at 2000 mA/g without significant capacity decay), and excellent rate performance. This study expands the high-entropy oxide family and provides a potential strategy for developing next-generation energy storage materials.

Treatment of high-concentration semi-coke wastewater by phenolic condensation and persulfate oxidation

In this study, the combined process of phenolic condensation-persulfate(PS) advanced oxidation was adopted to treat semi-coking wastewater. Using the phenolic condensation method as a pretreatment unit to remove phenolic substances for the preparation of phenol-formaldehyde resins, and using an aerated/PS/pyrite oxidation system as a deep treatment unit to remove chemical oxygen demand (COD) and ammonia nitrogen (NH3-N) from the wastewater. Analysis and characterization of phenol-formaldehyde resin, organic compounds in wastewater, and pyrite using FT-IR, TG-DTG, GC-MS, and XPS techniques. The results showed that under the conditions of adding 1.8vt % formaldehyde, pH 10.5, reaction temperature 95 ℃ and reaction time 3 h, the removal rates of volatile phenol, COD and NH3-N in semi-coke wastewater were 97.54 %, 41.14 % and 56.50 %, and the yield of phenolic resin was 6.62 g/L. Subsequently, treated with an aerated/PS/pyrite system, the PS concentration 0.4 mol/L, the pyrite dosage 15 g/L, the pH 3, the temperature 65 ℃, and the aeration 3 h, the removal rates of COD and NH3-N are 99.20 % and 86.80 %. In the phenolic condensation process, phenolic substances in semi-coke wastewater generate phenoxy anions under the influence of OH-, which undergo addition reactions with formaldehyde to produce hydroxymethyl phenol. Hydroxymethyl phenol further undergoes condensation reactions with other phenolic substances and itself to form phenolic resin, while amide compounds are generated through reactions between ammonia nitrogen and carboxylic acid substances. In the aeration/PS/pyrite system, Fe2+ released from pyrite oxidation activates PS to produce SO4•− and O2•−. The contribution of free radical oxidation and decomposition of pollutants such as phenols, amides, and NH3-N in wastewater is 84.60 %. Specifically, SO4•− oxidation contributes 61.54 %, while O2•− accounts for 22.21 %. Amide compounds and phenolic substances in the wastewater are oxidized, leading to ring opening and chain scission, resulting in the formation of alkane compounds.

Mitochondrial Dysfunction Plays a Relevant Role in Heart Toxicity Caused by MeHg.

The effects of methylmercury (MeHg) on exposed populations are a public health problem. In contrast to widely studied neurological damage, few cardiovascular changes have been described. Our group evaluated the cardiotoxicity of a cumulative dose of 70 mg.kg-1 fractioned over a 14-day exposure period in mice (MeHg70 group). The effects of MeHg on proteins relevant to cardiac mitochondrial function were also investigated. The results obtained showed a reduction in oxygen consumption in the two settings. In cardiac tissue samples in oxygraphy studies, this reduction was related to a lower efficiency of complexes II and V, which belong to the oxidative phosphorylation system. In vivo, mice in the MeHg70 group presented lower oxygen consumption and running tolerance, as shown by ergometric analyses. Cardiac stress was evident in the MeHg70 group, as indicated by a marked increase in the level of the mRNA encoding atrial natriuretic peptide. Electrocardiogram studies revealed a lower heart rate at rest in the animals from the MeHg70 group, as well as prolonged left ventricular depolarisation and repolarisation. Through echocardiographic analysis, reductions in the left ventricular ejection fraction and left ventricular wall thickness of approximately 10% and 20%, respectively, were detected. These results indicate that the oral intake of MeHg can decrease cardiac function and oxidative metabolism. This finding highlights the importance of monitoring MeHg levels in humans and animals in contaminated areas, as well as periodically carrying out cardiac function tests.

Correlation Of NAG, NGAL, and Oxidative Parameters For Patients With Diabetic Nephropathy

Background: Diabetic nephropathy is a clinical syndrome that is present in diabetic mellitus patients and characterized by albuminuria {>200 or >300 mg\day}, a gradual glomerular filtration rate decline along with hypertension. Objective: Study the correlation between N_acetyl-ß-D-glucamindase and human neutrophil gelatinase-associated lipocalin and oxidative parameters in diabetic nephropathy patients compared with a control group and several variables by Explaining the results scientifically. Method: The blood sample was collected from forty-five diabetic nephropathy patients and forty-five controls from Merjin Medical Hospital and Al-Imam Al-Sadiq Hospital in Iraq to assess N-acetyl-β-D-glucosaminidase and human neutrophil gelatinase-associated lipocalin levels by used Enzyme-Linked immunosorbent Assay technicality (ELISA) and also to determine the oxidative parameters (total oxidant system, total antioxidant capacity, malondialdehyde and glutathione) by used spectrophotometer. Result: positive correlation for N-acetyl-β-D-glucosaminidase with total oxidant status and malondialdehyde where the correlation coefficient (r=0.893**, 0.809**) at respectively and negative correlation with total antioxidant capacity and glutathione where the (r=-0.851**, -0.465**) at respectively, and exact correlation for human neutrophil gelatinase-associated lipocalin with total oxidant status, malondialdhyde, total antioxidant capacity, glutathione. Conclusion: The assessment of NAG, NAGL, and oxidant parameters can provide crucial information for the early diagnosis, management, and therapy of these patients with diabetic nephropathy.

Investigation of Metal–H2O Systems at Elevated Temperatures: Part I. Development of a Solubility Apparatus Specialized for Super-Ambient Conditions

Abstract Metals used in aqueous environments where high temperatures and pressures are present are susceptible to corrosion. This is the case for nuclear power plants, especially CANDUTM reactors, where the liquid water systems can reach over 300 °C at pressures well above 101.325 kPa (1 atm). In such situations, failure to control corrosion has economic and safety consequences. To extend corrosion modeling tools, such as Pourbaix diagrams, to harsh aqueous conditions, there is a need for experimental thermochemical data performed at elevated temperatures. This is particularly true for metal and alloy systems where such information is unavailable or unreliable. A relatively simple approach to obtaining temperature dependent thermodynamic properties is the investigation of solid–liquid phase, or solubility, equilibria. However, this requires specially designed instrumentation that can withstand harsh temperatures and extreme pH conditions, while providing accurate data. In this work, an apparatus developed for super-ambient highly acidic and alkaline solubility experiments is presented. Solubility measurements were made in the zinc oxide system, which has been extensively studied. Using these equilibrium data and comparing to the literature, allowed the instrumentation and analysis process to be validated. In situ pH measurements using a constant volume, batch reactor system are described along with a brief presentation of the ZnO dissolution equilibria results at 85 °C (358.15 K).

Abnormally narrow peaks in TPR-H2 over Pt/CeO2: Experiment and mathematical modelling

The application and development of methods using hydrogen as a gas for testing active surface sites is of great interest in the study of oxide catalysts. In this work a systematic study of Pt/CeO2 catalysts, depending on the platinum loading and calcination temperature was carried out using the method of temperature-programmed reduction by hydrogen (TPR-H2). Experimental TPR-H2 curves demonstrated a complex structure over a wide temperature range, including the presence of abnormally narrow consumption peaks (ANCP-H2) at low temperatures. To describe the kinetics, mathematical modeling of H2 consumption by various platinum active centers has been used, including isolated platinum ions (single atoms) and PtOx clusters of 2D and 3D structures on the surface of ceria nanoparticles. We proposed a criterion that makes it possible to extend the analysis of the TPR-H2 curves for reducible metal-supported oxide systems and unambiguously establish the action of the autocatalytic mechanism in hydrogen consumption. The kinetics of ANCP-H2 by cluster PtOx centers with a half-width of several degrees on the base of the autocatalysis mechanism was described on the base of the proposed model. The simulations show that ANCP-H2 are described by synchronous fast formation of metallic centers that provide a sharp acceleration of H2 consumption. In general, the obtained results establish the fundamental aspects of the H2 interaction with heterogeneous catalysts and are of particular interest in the light of various practical applications of hydrogen energy.

Insight into the nonradical selective oxidation mechanism for versatile organic pollutants removal by perovskite activated peroxymonosulfate system

The heterogeneous catalysis of peroxymonosulfate (PMS) through nonradical pathway has shown many advantages in environmental remediation. It is necessary to unveil the factors affecting oxidation routes and selectivity toward different organic pollutants. Herein, a series of ABO3-type BiFexCo1-xO3 perovskite catalysts were fabricated via simple hydrothermal process to realize the changeover of catalytic activity and mechanism in PMS activation and pollutants oxidation. The as-prepared BiFe0.5Co0.5O3 (BFCO-3) achieved a 98 % removal efficiency of SMZ with a high kinetic constant (kobs = 0.334 min−1) in 10 min. The superior catalytic performance was ascribed to the introduction of bimetals at B-site, which enhanced electron donating capacity to PMS, confirming by d-band center calculations. Several parameters such as inorganic anions and humic acids affected the SMZ degradation slightly, owing that singlet oxygen was verified to be the primary reactive species in the BFCO-3/PMS system. Moreover, twelve organic pollutants including amoxicillin crystalline (AMX), cephalexin hydrate (CFX), ciprofloxacin (CIP), levofloxacin (LFX), Sulfadiazine (SDZ), sulfamethoxazole (SMZ), 4-acetamidophenol (ACP), benzoic acid (BA), bisphenol A (BPA), carbamazepine (CBZ), metronidazole (MNZ) and naproxen (NPX) were utilized to investigate the selective oxidation mechanism. A linear correlation between lnkobs and their half-wave potential (φ1/2) values (except for BA and MNZ) suggesting the dominant role of nonradical catalysis where phenolic compounds with lower anodic potential tend to lose electrons are more easily degraded. Furthermore, the reactive sites of representative SMZ for electrophilic species attack were precisely identified based on the Fukui index. And the degradation intermediates of SMZ were further determined by LC-MS/MS technology for proposing their degradation pathway and predicting ecotoxicity. This study not only provides an efficient advanced oxidation system for organic pollutants removal but also advances our understanding of the selective oxidation mechanism in nonradical-dominated catalytic process.

Holistic insight into the viability of employing cerium(IV) sulphate to oxidise toxic contaminants in effluent from the coal gasification process: Optimisation studies

The coal gasification (CG) process, while beneficial for producing syngas, poses environmental risks due to the production of highly toxic wastewater containing high concentrations of polycyclic aromatic hydrocarbons (PAHs), phenolics, and cyanides. This study examines the oxidation of pollutants in wastewater from a simulated underground coal gasification (UCG) process, with initial pollutant levels of pH 1.8, total cyanides 21.00 mg/L, total phenols 61.95 mg/L, heavy metals 7.68 mg/L, PAHs 2459 μg/L, and dissolved organic carbon (DOC) 148.0 mg/L. Three oxidation systems (Ce(SO4)2·4H2O, Ce(SO4)2·4H2O + H2O2, and Fenton process with FeSO4 + H2O2) were used to remove pollutants from wastewater from the coal gasification process. In the first system, the oxidising agent was Ce4+ ions, while in the second and third systems, where hydrogen peroxide was added, the oxidising agents were hydroxyl radicals. Using central composite design and response surface methodology (CCD/RSM), the most favourable oxidation conditions were identified for Ce(SO4)2·4H2O (35 min, Ce4+:C molar ratio of 5:1, pH 2.5, temp. 40 °C). For the Ce(SO4)2·4H2O + H2O2 system DOC:Ce4+:H2O2 molar ratio of 1:2:10. Results showed significant reduction in pollutants: Ce(SO4)2·4H2O reduced PAHs, phenols, cyanides, DOC, and heavy metals by 99.40 %, 99.97 %, 97.67 %, 65.34 %, and 90.01 %, respectively; Ce(SO4)2·4H2O + H2O2 achieved reductions of 99.91 %, 99.66 %, 98.14 %, 76.35 %, and 81.45 %; and the Fenton process achieved reductions of 99.91 %, 99.95 %, 95.07 %, 56.49 %, and 89.33 %. An application of alternative oxidation processes (Ce(SO4)2·4H2O and Ce(SO4)2·4H2O + H2O2) is a viable option in removing toxic pollutants with simultaneously cerium recovery.

Reactive oxygen species-inducing itraconazole and its anti-biofilm activity against resistant Candida parapsilosis sensu lato biofilm cells isolated from patients with recalcitrant onychomycosis.

Candida parapsilosis was introduced as the second most responsible for nail involvement. The colonization of biotic and abiotic surfaces by Candida spp.can result in the formation of biofilms, which possess a high level of resistance to typical antifungal agents. Since Candida spp. can produce biofilm mass on the surface of the nails, dermatologists should consider appropriate antifungals to eliminate both the planktonic and biofilm cells. The aim of this research was to determine the antifungal efficacy of itraconazole against C. parapsilosis sensu lato biofilm formations, in addition to its static effects. Ten C. parapsilosis sensu lato isolates were enrolled in this study. The use of itraconazole results in the accumulation of reactive oxygen species (ROS) during treatment. In order to verify the correlation between ROS and itraconazole-induced cell death, the viability of cells was analyzed by administering the ROS scavenger Ascorbic acid. The apoptotic features of itraconazole were analyzed using the Annexin V-FITC method. Based on current data, it was found that the generation of intracellular stresses by itraconazole is not observed in cells upon ROS inhibition, emphasizing the importance of intracellular ROS in the apoptotic mechanism of itraconazole. Targeting the oxidative defense system is a powerful point to use ROS-inducing antifungals as a superior choice for more effective therapies in case of recalcitrant onychomycosis.

Investigation of acid-activated iron-based bentonite materials for the oxidation mechanism of dimethyl disulfide

Due to its low olfactory threshold and high volatility, Dimethyl disulfide (DMDS) is a well-known malodorous compound in pesticides and organic synthesis. This study utilizes sodium bentonite as catalyst support, treating it with acid activation and iron-based modification to create a catalytically active bentonite material. Following modification, the bentonite maintains its fundamental structure while integrating iron ions, resulting in an expanded interlayer spacing and increased specific surface area from 60.371 m2/g to 314.539 m2/g, thereby enhancing catalytic activity. Kinetic modeling fitting demonstrates that combining iron-based acid-activated bentonite with hydrogen peroxide (H2O2) produces the most efficient oxidative system, with the highest reaction rate constant（K = 0.08038 min−1） for DMDS degradation. The best degradation effect was achieved when the ratio of Fe-H-Bent to hydrogen peroxide was 1:5, the pH was 3, and the reaction temperature was 40 °C, and the removal rate was up to 98.9%. Electron paramagnetic resonance (EPR) spectroscopy confirms that hydroxyl radicals (·OH) are this system's primary driver of oxidation. Theoretical computations and product analyses provide insight into the oxidation pathway of DMDS, showing that initial oxidation occurs at the first sulfur atom, forming an intermediate that further oxidizes to dimethyl sulfoxide and ultimately to sulfur dioxide. This research offers a practical method for the effective removal of DMDS in pesticide plants and chemical industrial parks.

Synergistic Degradation of Methylene Blue by Hydrodynamic Cavitation Combined with Hydrogen Peroxide/Vitamin C System.

In this study, a new combined process of hydrodynamic cavitation (HC) and a hydrogen peroxide/vitamin C (H2O2/Vc) system was proposed for the degradation of methylene blue (MB) in wastewater. An impact-jet hydraulic cavitator was used as the cavitation generation equipment, and H2O2/Vc was selected as a homogeneous oxidation system. The degradation characteristics of MB were investigated. The results showed that the degradation effect of HC in combination with the H2O2/Vc system was more effective than that of the individual HC or H2O2/Vc system. A maximum degradation rate of 87.8% was achieved under the following conditions: H2O2 concentration of 0.03 mol/L, Vc concentration of 0.021 mol/L, inlet pressure of 0.3 MPa, initial solution concentration of 4 μmol/L, solution volume of 150 mL, and reaction time of 10 min. The synergy index was 1.615, indicating a synergistic effect between the HC and H2O2/Vc system. The data of the hydroxyl radical (·OH) yield under the conditions of HC, the H2O2/Vc system, and the HC + H2O2/Vc system were fitted and analyzed. A correlation equation for ·OH yield was established, further revealing the synergistic mechanism of the HC and H2O2/Vc system. The intermediate products of MB degradation were detected based on LC-MS, and three possible degradation pathways of MB degradation were proposed. The combined process of HC and H2O2/Vc systems exhibited relatively low energy efficiency and operating cost, indicating that it was in line with the development direction of wastewater treatment.

In-situ ‘X’ doped ‘GCN’ photocatalyst enables selective aldehyde synthesis via photo-oxidation of benzyl alcohol under ambient conditions

Photo-oxidative selective conversion of benzyl alcohols using graphitic carbon nitride (GCN) is a sustainable strategy for conventional metal-doped heterogeneous catalytic oxidation systems. Non-metal doped graphitic carbon nitride (a subclass of GCN) enhances its properties as an efficient photocatalyst for oxidation. These heteroatom non-metal dopants alter the optical energy gap and chemical and electronic properties of GCN, making it ideal for creating cost-effective, practical utility. So, herein, we designed heteroatoms (X = B, S, C) doped GCN photocatalysts derived from melamine (M) with different heteroatom ingredients and compared their activity in detail. Among these, the photo-oxidation of benzyl alcohol under blue LED by S-doped GCN (S-GCN) photocatalyst exhibits utmost higher photocatalytic activity than other heteroatoms doped GCN photocatalyst due to suitable band gap and slow photoinduced charge carriers recombination. The suitable energy gap with higher chemical stability is accountable for the substantial increase in the photocatalytic efficiency of S-GCN in the solar light responsive integrating reactions of oxidation of benzyl alcohol in aerobic conditions. Attaining an exceptional >99 % selectivity towards benzaldehyde (up to 5 cycles without significant loss of activity) marks a remarkable milestone. This opens up new possibilities for using these simple non-metal-doped photocatalysts in fine chemical synthesis.

Characterization and functional analysis of Litopenaeus vannamei Na+/K+/2Cl− cotransporter 1 under nitrite stress

The function of Litopenaeus vannamei Na+/K+/2Cl− cotransporter 1 (NKCC1) under nitrite stress was investigated. The full-length cDNA sequence of the L. vannamei NKCC1 gene was cloned using the rapid amplification of cDNA ends (RACE) technique, and the sequence was analysed using bioinformatics tools. Expression and localisation of NKCC1 in tissues were assessed using real-time quantitative PCR and in situ hybridisation, respectively. The impact of nitrite stress on the survival, physiology, biochemistry and tissue structure of L. vannamei was investigated following silencing of NKCC1 by RNA interference. The 3143 bp cDNA sequence of L. vannamei NKCC1 encodes a polypeptide of 918 amino acids. It is evolutionarily conserved. NKCC1 expression was highest in gill tissue, particularly within cuticle and gill epithelial cells. After silencing NKCC1, an increase in shrimp survival was observed, accompanied by a significant reduction in nitrite entry into the body (P < 0.05). Moreover, the oxidative stress enzyme system remained unaffected and damage to gill tissue was alleviated. The results suggest that NKCC1 is involved in regulating nitrite uptake, and plays a crucial role in facilitating nitrite entry into the organism through gill tissue. The findings provide a vital experimental basis for addressing concerns related to nitrite toxicity.

Multi-omics joint analysis reveals that the Miao medicine Yindanxinnaotong formula attenuates non-alcoholic fatty liver disease

BackgroudNon-alcoholic fatty liver disease (NAFLD) is a growing chronic liver disease worldwide, and no effective agent is approved yet for this condition. Traditional Chinese Medicine (TCM), which has been practiced for thousands of years in China and other Asian countries, is considered an important source for identifying novel medicines for various diseases. Miao medicine Yindanxinnaotong formula (YDX) is a classical TCM for the treatment of hyperlipidemia disease by reducing blood lipid content, while the role of YDX have not been clarified in NAFLD. PurposeTo investigate the protective effect of YDX on NAFLD in mice induced by high fat diet (HFD) and clarify the potential mechanism. MethodsNAFLD mice model was constructed by receiving HFD for 10-week period with or without YDX administration. Lipid profiles, biochemical indicators, and histopathological staining were performed to evaluate the extent of hepatic lipid accumulation and hepatic steatosis. 16S rRNA sequencing was used to determine the gut microbial composition. Serum metabolomics was further used to investigate the changes in plasma biomarkers for NAFLD-associated by UPLC-Q-TOF/MS analysis. Subsequently, liver transcriptomics was employed to identify differentially expressed genes and explore regulatory pathways. Then, lipid metabolism–related proteins and inflammation factors were examined by Western blot and ELISA. ResultsYDX reduced body weight gain, liver index and inflammatory cytokines levels, along with improved hepatic steatosis, serum lipid profile, sensitivity to insulin and also tolerance to glucose, and enhanced oxidative defense system in HFD-induced mice. Also, YDX remarkedly affected gut microbiota diversity and community richness and decreased the ratio of Firmicutes/Bacteroidetes. Meanwhile, YDX also reduced the production of harmful lipid metabolites in the sera of NAFLD mice, such as LPC(18:0), LPC(18:1) and carnitine. Notably, consistent with liver transcriptomics results, YDX downregulated the expression of proteins implicated in de novo lipid synthesis (Srebp-1c, Acaca, Fasn, Scd-1, and Cd36) and pro-inflammatory cytokines (IL-6 and TNF-α), and increased the expression of proteins-related fatty acid β-oxidation (Ampkα, Ppar-α, and Cpt-1) in the liver by activating Ampk pathway. ConclusionYDX is promisingly an effective therapy for preventing NAFLD by modulating the Ampk pathway, inhibiting gut microbiota disorder, and reducing the production of harmful lipid metabolites.

Advanced electrochemical oxidation of EDTA-Ni via cobalt single-atom catalysts: Exploring indirect persulfate activation pathways

This study explores an innovative electrochemical strategy for the removal of the highly stable and toxic EDTA-Ni complex found in electroplating wastewater. Utilizing a cobalt-based single-atom catalyst (Co-NC) in an electro-enhanced system, we achieved significant activation of peroxydisulfate (PDS) for effective degradation of EDTA-Ni. Under optimal conditions of 40 mA current density and a pH range of 3–7, more than 97% of EDTA-Ni (1 mM) was successfully degraded within 90 min. Through detailed electrochemical experiments, we identified that atomic hydrogen (H*) played a crucial role in the indirect activation of PDS, facilitating the formation of reactive sulfate radicals (·SO4-). Computational analysis using density functional theory (DFT) confirmed that the H*-mediated reduction pathway had a notably low energy barrier (ΔGbs = 0.51 eV), making it the dominant activation mechanism. Gas chromatography-mass spectrometry (GC–MS) further revealed the primary degradation intermediates, providing insights into the breakdown process of EDTA-Ni. This research underscores the potential of Co-NC catalyst as a highly effective catalyst for treating persistent heavy metal complexes in advanced oxidation systems.