Search Results (3,174)

In this work, a BiFeO₃/MoS₂ (BM) material was utilized to establish a piezophotocatalytic system under combined visible-light (Vis) illumination and mechanical stirring (MS), which synergistically activated peroxymonosulfate (PMS) toward the oxidation of 4-chlorophenol (4-CP), a representative refractory organic pollutant in water. Under mechanical stirring, the piezoelectric effect in BM generates a polarized electric field that promotes the separation of photogenerated electron–hole pairs, thereby providing more charge carriers for PMS activation and subsequent radical generation. The degradation performance, underlying mechanism, toxicity of degradation products, reusability, and applicability in different water matrices in the BM(1:3)/PMS process were comprehensively evaluated. The results indicated that BM(1:3) exhibited superior performance over other BM ratios (BM(2:1), BM(1:1), and BM(1:2)), achieving 91.6% removal of 4-CP within 30 min at a rotation speed = 1000 rpm, PMS = 2.0 mM, BM(1:3) = 0.5 mg/L, and initial 4-CP = 10 mg/L. Furthermore, water quality parameters exerted notable impacts on 4-CP decomposition. A pH of 4.7 was favorable, and the presence of Cl⁻ enhanced the 4-CP degradation, while HCO₃⁻ and H₂PO₄⁻ suppressed the removal efficiency; SO₄²⁻ and HA showed negligible influence. DFT calculations identified the reactive sites on 4-CP that are prone to attack by various reactive oxygen species (e.g., •O₂⁻, ¹O₂, •OH, and SO₄•⁻), resulting in the transformation of 4-CP through three degradation pathways into smaller organic intermediates, most of which were less toxic than 4-CP. The BM(1:3) catalyst exhibited satisfactory reusability; however, a significant decrease in 4-CP degradation efficiency was observed in the lake water matrix. Overall, the synergy between photocatalysis and the piezoelectric effect in the BM(1:3)/PMS system offers a useful research foundation for the piezophotocatalytic degradation of persistent organic pollutants such as 4-CP. Full article

In this work, we aim to enhance the photocatalytic performance of SrTiO₃ by constructing a heterojunction with photoactive BiOBr. The novelty of this study lies in demonstrating the dual functionality of the SrTiO₃/BiOBr heterojunction in both photocatalytic tetracycline degradation and antibacterial applications and correlating its performance with its interfacial electronic properties. A SrTiO₃/BiOBr (50STO) heterojunction was successfully synthesized by combining microwave-assisted sol–gel-derived SrTiO₃ with co-precipitated BiOBr via solid-state calcination. XRD analysis revealed that the synthesized composite consisted of crystalline cubic SrTiO₃ and tetragonal BiOBr, confirming the successful formation of a 50STO heterojunction while preserving the crystal structures of both components. PL and EIS analyses revealed modified charge-carrier behavior, further supporting the successful formation of the 50STO heterojunction. XPS confirmed the chemical states of the constituent elements and revealed changes in the surface chemical environment following the coupling of SrTiO₃ with BiOBr. SEM, elemental mapping, and UV–Vis DRS analyses demonstrated uniform elemental distribution, enhanced visible-light absorption, suppressed electron–hole recombination, and improved interfacial charge transfer. Consequently, the optimized 50STO composite achieved 45% tetracycline degradation under visible-light irradiation within 150 min, whereas pristine SrTiO₃ degraded only 2%. The apparent reaction rate constant increased from 6.11 × 10⁻⁷ to 3.2 × 10⁻³ min⁻¹, while the heterojunction remained stable over five reuse cycles. Radical scavenging and LC–MS analyses identified h⁺ and •OH as the dominant reactive species and revealed successive tetracycline degradation. The composite also exhibited excellent antibacterial activity against E. coli under white-light irradiation. Full article

Ammonia, a toxic and volatile pollutant commonly found in chemical industrial environments, requires reliable real-time detection to ensure industrial safety and effective environmental monitoring. Conventional gas sensors typically operate at elevated temperatures, resulting in high power consumption. Moreover, pure metal oxides and conductive polymers often suffer from significant aggregation and exhibit suboptimal sensing performance under ambient conditions, limiting their practical applications. In this study, hierarchical porous V₂O₅/PANI composites were synthesized via a straightforward one-step coprecipitation method combined with in situ polymerization. The interlaced architecture of polyaniline (PANI) and vanadium pentoxide (V₂O₅) effectively reduces structural aggregation and increases the availability of surface active sites. Furthermore, the synergistic interaction at the bi-phase interface significantly enhances charge carrier transport, leading to improved ammonia-sensing capabilities at room temperature. Notably, the composite containing 20% V₂O₅ demonstrated superior response, selectivity, and reproducibility toward 10 ppm NH₃. Due to its simple fabrication process and room-temperature operation without external heating, the developed V₂O₅/PANI composite sensor holds significant potential for practical applications in low-concentration ammonia detection under ambient conditions. Full article

Using bismuth oxide (Bi₂O₃) as the matrix and employing a doping modification strategy to introduce the rare-earth element La, this study prepared La/Bi₂O₃ visible-light-responsive photocatalysts with different doping ratios. The research systematically investigated the regulation mechanisms of La doping on the material’s phase structure, microstructure, band structure characteristics, and visible-light photocatalytic performance. The results indicate that an appropriate amount of La³⁺ equivalently substitutes Bi³⁺ in the lattice, inducing the complete transformation of pure α-Bi₂O₃ into the tetragonal β-Bi₂O₃ phase while maintaining the integrity of the crystal framework. Meanwhile, the modulation of the local electronic structure caused by La³⁺ substitution effectively narrows the bandgap width and broadens the visible-light response range; it also acts as an electron trap to significantly suppress the recombination of photo-generated electron–hole pairs, thereby enhancing charge transport efficiency. Visible-light catalytic degradation experiments confirmed that 4% La/Bi₂O₃ exhibits the optimal degradation kinetics for RhB, achieving a 72.88% degradation rate of Rhodamine B within 60 min of visible-light irradiation. The first-order reaction rate constant was 23 times that of pure Bi₂O₃, and the material demonstrated good stability under repeated cycles. Radical trapping experiments indicated that the order of contribution of active species was ·O₂⁻ > h⁺ > ·OH, with the superoxide radical (·O₂⁻) being the dominant active species. This study confirms that appropriate lattice doping with La can synergistically optimize the structure and optoelectronic properties of Bi₂O₃, providing experimental evidence and theoretical references for the rational design of highly efficient and stable visible-light-responsive Bi₂O₃-based photocatalytic materials. Full article

Two diastereoisomers of bis(mepirizole)bis(isothiocyanato-κ,N)cobalt(II) (1 and 2) are isolated from the reaction of cobalt(II) thiocyanate and mepirizole, depending on the crystallization solvent (ethanol, 1; acetonitrile, 2). In both crystal structures, the Co(II) ions exhibit distorted octahedral [CoN₄N′₂] environment. The analysis of the packing frameworks shows a cooperative relationship between non-classical H-bonds C(sp³)-H···X (X = N, O, S, π) and π-hole bonds, which control the arrangement of the supramolecular 3D networks. The values of the shortest intermolecular metal–metal separation are 8.584(2) Å in 1 and 8.249(1) Å in 2. Both diastereoisomers exhibit magnetic behavior typical of mononuclear Co(II) systems with significant zero-field splitting (ZFS) values, with D being 75.8(1) and 52.9(2) cm⁻¹ for 1 and 2, respectively. Q-band EPR studies confirm the positive value for the D parameters for both compounds. Alternating current dynamic susceptibility measurements show that 1 and 2 exhibit field-induced slow relaxation of the magnetization, which is reminiscent of single-ion magnet (SIM) behavior. Full article

The practical viability of lithium–sulfur batteries (LSBs) is severely hindered by sluggish liquid–solid conversion kinetics and the polysulfide shuttle effect. Herein, we report an in situ-derived ferroelectric-semiconductor Bi₄Ti₃O₁₂-Bi₂S₃ heterojunction as a multifunctional separator coating. The intimate atomic-level coupling at the heterointerface generates a built-in electric field that, synergizing with the spontaneous ferroelectric polarization of Bi₄Ti₃O₁₂, structurally intensifies polysulfide chemisorption and lowers the activation energy for bi-directional Li₂S precipitation/dissociation. Furthermore, the localized polar field appears to homogenize lithium-ion flux, which may contribute to improved lithium anode stability. Consequently, cells featuring the modified separator deliver a high initial capacity of 1172 mAh g⁻¹ at 0.5 C and demonstrate good cycling stability over 500 cycles with a low capacity decay rate of 0.096% per cycle. This in situ interfacial engineering offers a promising kinetic regulatory strategy for improving the performance of LSBs. Full article

Indole alkaloids are major bioactive compounds in Strobilanthes cusia. Although methyl jasmonate treatment can promote the accumulation of indole alkaloids in S. cusia, the transcriptional regulation remains unclear. In this study, the jasmonic acid responsive bHLH transcription factor ScMYC2 was cloned and characterized. It encodes a protein containing 477 amino acids, which features typical bHLH-MYC_N and HLH domains. ScMYC2 localized in the nucleus, showed tissue specific expression consistent with indole alkaloid accumulation, and was significantly induced by methyl jasmonate. Furthermore, the coding sequence of ScMYC2 was cloned into an expression vector and overexpressed in Arabidopsis thaliana via Agrobacterium-mediated transformation technology. Alkaloid metabolic analysis was performed on three homozygous A. thaliana lines (ScMYC2-OE1, OE2, OE3) stably transformed using UPLC-MS/MS. The results indicated that, compared with wild-type, 14 differential metabolites were detected in the A. thaliana lines overexpressing ScMYC2. Among them, the content of indole increased to 2.83-fold that of the wild-type, while the indole glycoside component indole-3-cyano-6-O-glucoside increased to 2.35-fold. Yeast two-hybrid screening identified 35 ScMYC2-interacting proteins, including UDP-glycosyltransferase, TOPLESS-related proteins, and E3 ubiquitin-protein ligase. BiFC assays further confirmed the in vivo interaction between ScMYC2 and ScUGT1. These findings suggest that ScMYC2 is associated with methyl jasmonate-responsive regulation of indole alkaloid biosynthesis and provides genetic resources for the cultivation of S. cusia with high medicinal value. Full article

Branch prediction errors can reduce superscalar throughput by more than the error frequency alone suggests because a single misprediction can trigger redirect, squash, refetch, refill, and window recovery, which collectively disrupt sustained instruction-level parallelism. This paper presents a quantitative framework that relates prediction accuracy to realized parallelism loss in out-of-order superscalar processors. The framework separates prediction-error frequency, effective recovery cost, and unrealized issue capacity using prediction accuracy (Acc), misprediction rate (MR), effective branch penalty in cycles per misprediction (BP), parallelism loss ratio (PLR), the ratio-based branch sensitivity factor $BSF=PLR/MR$, and the slope-based branch sensitivity factor $\mathit{S-BSF}=\mathit{\partial }PLR/\mathit{\partial }MR$. BSF measures how strongly a particular processor configuration and workload convert prediction errors into lost issue capacity, whereas S-BSF provides a more stable sensitivity estimate when MR approaches zero. The framework is evaluated using timing-detailed gem5 O3 simulations on RV64GC workloads. The evaluation includes controlled branch microbenchmarks and six GAPBS graph workloads, allowing the proposed metrics to be examined under both mechanism-isolating and complex workload conditions. Two complementary controlled sweeps are used. At a fixed processor structure, predictor family and predictor level are varied to determine whether changing the predictor strengthens or weakens the relationship between MR and IPC/PLR. At a fixed predictor configuration, issue width and an effective front-end-depth proxy are varied to measure how the microarchitecture amplifies the performance cost of the remaining prediction errors. Thus, issue width is treated as an amplification variable for branch-prediction failures rather than as an independent performance topic. At the fixed structural point, Tournament and BiMode predictors show strong monotonic MR–PLR relationships on the high-branch benchmark, with Spearman coefficients of 1.00 and 0.98, whereas the Local predictor exhibits nearly unchanged MR but materially different IPC and PLR across levels. This demonstrates that the mapping from MR to throughput depends on predictor family and configuration rather than being invariant. In the controlled structural sweep, increasing issue width from 4 to 8 raises PLR by 37.6% and BSF by 55.0% on the high-branch benchmark, even though MR remains in the same order of magnitude. On GAPBS workloads, the lowest-MR configuration is not always the highest-IPC configuration, confirming that effective branch penalty and parallelism loss must be considered together with prediction frequency. These numerical findings are conditional on the evaluated single-thread gem5 DerivO3CPU model, RV64GC binaries, predictor implementations, memory hierarchy, and workload set. They characterize predictor–microarchitecture interactions in this controlled simulation environment and should not be interpreted as universal constants for all processors or applications. Full article

The electrocatalytic reduction of CO₂ into value-added chemicals offers a promising route to mitigate greenhouse gas emissions, yet the uncontrollable structural reconstruction and surface rearrangement of electrocatalysts during operation often lead to severe activity degradation. Herein, we reveal that Bi₂O₂SO₄ (BSO) undergoes an irreversible phase transformation into Bi₂O₂CO₃ (BCO) nanosheets accompanied by the partial reduction of Bi³⁺ to metallic Bi⁰ under cathodic potentials. A series of BCO/BSO heterojunction catalysts with tunable compositions are synthesized via a mild in situ ion-exchange method. To circumvent the detrimental effects of this dynamic reconstruction, we devise a pre-activation strategy that deliberately completes the structural evolution prior to electrocatalysis. The optimized 20%-BCO/BSO heterojunction achieves a remarkable Faradaic efficiency of 98.4% for formate production in a flow cell at elevated potentials, with >95% FE_(HCOOH) over a wide potential window (−0.8 to −1.7 V vs. RHE). In situ infrared spectroscopy elucidates that the reconstructed interface can promote CO₂ adsorption, stabilize the *OCHO intermediate, and facilitate HCOOH desorption. This work provides experimental evidence of the reconstruction behaviour of bismuth-based catalysts and offers a rational design method for constructing structurally stable heterojunction electrocatalysts. Full article

The coordination chemistry of “salen-type” Schiff bases with the uranyl ion, trans-{U^VIO₂}²⁺, attracts the interest of several inorganic chemistry groups worldwide for a variety of reasons. The full synthetic investigation of the {UO₂}²⁺/H₂L reaction system, where H₂L is bis(2-hydroxyacetophenone)ethylenediamine, has provided access to complexes [UO₂(L)(EtOH)] (1) and [UO₂(L)(DMF)] (2) in moderate to good yields. The molecular structures of the two complexes are similar. The U^VI atoms are bonded to five oxygen and two nitrogen atoms in a distorted pentagonal bipyramidal geometry. The two uranyl oxo(or oxido) atoms occupy the axial positions, and the {O=U=O}²⁺ moiety is almost linear. The equatorial donor atoms are the two oxygens and the two nitrogens from the tetradentate chelating (1.1111 using Harris notation) L²⁻ ligand, and the oxygen atom of the coordinated solvent molecule. H-bonded dimers of 1 exist in its crystal structure. The complexes were fully studied in the solid state by IR, Raman, UV/Vis (diffuse reflectance) and emission spectroscopies, and the data are discussed in terms of the known structural data of the complexes and the coordination modes of the ligands. The structures of the complexes persist in solution as evidenced by NMR (¹H, ¹³C{¹H}) and UV/Vis spectroscopies, as well as by molar conductivity data. Complexes 1 and 2 exhibit moderate photocatalytic activity towards the degradation of the model organic dye methylene blue under continuous UV irradiation in aqueous media. The reaction kinetics were fitted using the Langmuir-Hinshelwood pseudo-first-order model. Combined IR and powder X-ray diffraction data show that the photocatalyst 1 remains unchanged after the photocatalytic experiment, whereas 2 undergoes DMF leaching. Based on literature reports, a simplified single-electron transfer mechanism has been proposed for the photocatalytic activity. Full article

With the rapid development of Industrial Internet-oriented smart energy systems, hydro-turbine generator units are increasingly monitored through networked sensors, industrial communication infrastructures, and edge/cloud-based condition-monitoring platforms. These Internet-connected monitoring environments provide abundant vibration data for intelligent operation and maintenance (O&M) but also introduce a challenging unsupervised cross-scenario diagnosis problem. Specifically, diagnostic models trained on labeled historical data may suffer severe performance degradation when deployed to unlabeled online data collected under different hydraulic conditions, rotational speeds, or operating conditions. Furthermore, existing domain adaptation methods, in their pursuit of distribution alignment, frequently overlook a critical bottleneck that limits generalization performance: inter-class entanglement. Specifically, under intense hydraulic background noise and cross-condition distribution shifts, features belonging to distinct fault types are highly susceptible to aliasing within the feature space. To overcome these issues, this paper proposes a Conditional Wasserstein Adversarial Network with Bi-level Prototype Disentanglement Regularization (CWAN-BPDR). First, a Conditional Wasserstein Adversarial Network (CWAN) is constructed by combining the smooth-gradient property of Wasserstein distance with conditional adversarial alignment, thereby achieving stable and fine-grained category-level domain adaptation. Furthermore, to alleviate the inter-class entanglement problem that may arise during cross-domain alignment, a Bi-level Prototype Disentanglement Regularization (BPDR) term is designed. By jointly implementing source–target prototype alignment and prototype–feature bidirectional alignment, BPDR explicitly suppresses inter-class confusion and enhances intra-class compactness and inter-class separability in the feature space. Experimental results on the JNU and NEFU datasets demonstrate that CWAN-BPDR achieves average diagnostic accuracies of 97.82% and 98.99%, respectively, while significantly mitigating label entanglement in challenging cross-operating-condition tasks. These results indicate that the proposed method can effectively transfer diagnostic knowledge acquired from labeled historical operating conditions to unlabeled online monitoring data. It can therefore serve as an offline-trained diagnostic module for Industrial Internet of Things-based condition-monitoring platforms in hydropower systems. Full article

Background: Terminal sterilization is a regulatory requirement for most medical devices. However, conventional sterilization methods can compromise temperature-sensitive and biologically reactive components. This study evaluates the sterilization efficacy and preliminary material compatibility of a novel room-temperature sterilization modality using gaseous nitric oxide (NO). Methods: NO was delivered using standardized Sterile Solution^® (Sterile State Inc., Grand Rapids, MI, USA). To characterize microbial inactivation kinetics, the decimal reduction time (D-value) of commercial biological indicators (BIs), Bacillus atrophaeus Apex^® Discs, was determined in accordance with ISO 11138. BIs were exposed to NO at ambient temperature (18.9–22.0 °C). D-values were calculated using both the survivor curve method (Holcomb–Spearman–Karber) and the fraction-negative method (Stumbo–Murphy–Cochran). Material compatibility was evaluated across four primary medical device and packaging plastics, including polyethylene (PE), poly(ethylene terephthalate) (PET), polypropylene (PP), and polyvinyl chloride (PVC)), representing 70% of the industry market share. After exposure to NO sterilization cycles, mechanical and chemical properties were characterized using tensile testing (ASTM D882-18) and Fourier-transform infrared (FTIR) spectroscopy relative to unexposed controls. Results: The calculated D-values ranged from 1.31 (78.7 min) to 1.34 h (80.4 min) across both analytical methods, corresponding to an estimated 6-Log reduction in Bacillus atrophaeus BIs in approximately 8 h. Meanwhile, plastics exposed to the NO sterilization cycle showed no significant changes in mechanical or chemical properties. Conclusions: These findings demonstrate that NO sterilization achieves semi-Log-linear inactivation of a widely accepted BI and represents a promising alternative to conventional gaseous sterilization methods such as ethylene oxide (EtO). By achieving a reliable sterility assurance level under mild ambient conditions without adversely affecting the physicochemical properties of commonly used plastic materials, NO sterilization may offer a practical solution for thermosensitive and delicate medical devices. Full article

The crystal structure and physicochemical properties of a new Ni/Zn codoped bismuth antimonite pyrochlore, synthesized by the solid-phase reaction method, were investigated. The most optimal outcomes of Rietveld refinement for Bi_2.7Zn_0.46Ni_0.70Sb₂O_10+Δ were achieved for the model of a disordered pyrochlore structure (sp.gr.Fd-3m:2, a = 10.46442(5) Å). Zinc and nickel atoms demonstrate an inhomogeneous mixed distribution across bismuth and antimony positions. The microstructure of the ceramic is characterized by low porosity, and is formed by faceted grains of 0.25–2 μm in diameter. The thermal expansion coefficient (TEC) increases monotonically from 7.14 × 10⁻⁶ °C⁻¹ (30 °C) to 9.80 × 10⁻⁶ °C⁻¹ (990 °C). At temperatures above 1080 °C, an atypical thermal dissociation of the pyrochlore occurs, resulting in the formation of bismuth-free compounds and two cubic phases that are stable when the sample is cooled. The Bi_2.7Zn_0.46Ni_0.70Sb₂O_10+Δ compound is characterized by a band gap width of 2.4 eV. At temperatures below 200 °C, the sample exhibits predominantly capacitive impedance characteristics. The capacitance remains constant and independent of temperature and frequency up to a maximum of 150 °C. The high-frequency relative dielectric permittivity is low and equal to 26(3). The conduction activation energy in the sample is found to be 1.30(5) eV. Two polarization processes are detected in the sample. The electrical behavior of the sample has been modeled successfully by equivalent circuits within the temperature range of 200–450 °C. According to NEXAFS and XPS data, metal cations exhibit a conventional charge state, with an antimony oxidation state of +(5−δ). Full article

Substituted p-phenylenediamine-quinones (PPD-Qs) are commonly employed as antioxidants in varying rubbers with potential biotoxicological implications in humans. Associations between human PPD-Q exposure and oxidative stress and immune system modulation remain insufficiently characterized. This study investigated the human exposure profile of six PPD-Q homologues and their associations with malondialdehyde (MDA) and immune function biomarkers in a general adult population from Quzhou, China. The six target PPD-Qs were detected in most human serum samples (n = 205), with 2-((4-methylpentan-2-yl)amino)-5-(phenylamino)cyclohexa-2,5-diene-1,4-dione (6PPD-Q) emerging as the dominant compound (mean 1.67 ng/mL; range < LOD–5.46 ng/mL). Serum MDA levels showed significant positive correlations with several PPD-Qs, such as 6PPD-Q, 2,5-bis(o-tolylamino)cyclohexa-2,5-diene-1,4-dione (DTPD-Q), and 2,5-bis(phenylamino)cyclohexa-2,5-diene-1,4-dione (DPPD-Q), suggesting enhanced oxidative stress in humans. Moreover, the serum C-reactive protein level was positively associated with DTPD-Q, 77PD-Q (2,5-bis((5-methylhexan-2-yl)amino)cyclohexa-2,5-diene-1,4-dione), and DPPD-Q; IgA was negatively associated with CPPD-Q (2-(cyclohexylamino)-5-(phenylamino)cyclohexa-2,5-diene-1,4-dione) and 6PPD-Q; IgM was negatively associated with DPPD-Q and 6PPD-Q. These findings provide the first human correlational evidence suggesting associations between PPD-Q exposure and oxidative stress- and immune-related biomarkers, highlighting the need for further research and regulatory attention regarding these tire-derived pollutants. Full article

Prunus salicina × P. armeniaca, an interspecific hybrid of Chinese plum and apricot, shows substantial variation in peel and flesh color and quality traits. Ten cultivars were characterized by integrating physicochemical measurements, spectrophotometric assays of phytochemical content and antioxidant capacity, and widely targeted ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) metabolite profiling. Tissue type was the main source of chemical variation. Peel contained higher total phenolic (TPC), flavonoid (TFC), and anthocyanin (TAC) contents and greater 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging capacity, 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical-scavenging capacity, and ferric reducing antioxidant power (FRAP), whereas flesh showed higher relative abundances of sugars, sugar alcohols, organic acids, amino acid derivatives, lipids, nucleotides, and terpenoids. Among 248 annotated metabolites, flavonoids were predominant, and color-related differentially accumulated metabolites were mainly enriched in phenylpropanoid and flavonoid pathways, particularly in purple–yellow comparisons. Integrating tissue-specific correlations, random forest models, and color-gradient patterns prioritized cyanidin-3-O-glucoside, dihydromyricetin, genistin, and orientin as cross-tissue color-associated metabolites. Cyanidin-3-O-glucoside showed the strongest association with coloration and anthocyanin content, whereas 4′-O-glucosylvitexin was strongly connected with phenolic, flavonoid, anthocyanin, and antioxidant traits. Comprehensive nutritional quality index rankings further distinguished cultivar-specific peel and flesh quality profiles. These results provide a tissue-resolved metabolic basis for evaluating and utilizing plum–apricot hybrid germplasm. Full article