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Lead-free (Ba 0.85 Ca 0.15 )(Ti 0.9 Zr 0.1 )O 3 -xwt%CuOywt%Y 2 O 3 (BCZT-Cu x Y y ) ceramics with high piezoelectricity were synthesized by the conventional solid-state reaction method. The role of Cu and Y (Cu/Y) in sintering, phase transition, and electrical properties of such ceramics was systematically studied. The results indicated that the sintering temperatures of BCZT-Cu x Y y decreased by at least 100 °C due to the low melting point of CuO. The promotion effect of Cu/Y on phase transition lied in the improvement of T C by 5–15 °C and the coexistence of O+T phase near room temperature. The contribution of Cu/Y to electrical properties was mainly ascribed to the grains growth, the formed oxygen vacancies and lattice distortions, and the donor doping effect of Y 3+ . Adding 0.10 wt% Cu 2+ and 0.06 wt% Y 3+ into BCZT dramatically improved the electrical properties as following: d 33 = 552 pC/N, ε m = 10175, ε r = 4546, tanδ = 0.016, T C = 100 °C, k p = 0.475, Q m = 157.2, P r = 10.82 μC/cm 2 and E C = 2.33 kV/cm. A plausible mechanism was obtained to explain the reaction process and the favorable performances of BCZT-Cu x Y y . Co-doping Cu 2+ and Y 3+ into BCZT could be a promising method to improve and balance the sintering, phase transition, and electrical properties for potential practical applications of lead-free piezoceramics. [ABSTRACT FROM AUTHOR]

Abstract: Spatial distribution of nonylphenol polyethoxylates (NPEOs) and nonylphenol (NP) was investigated in a field study in Lanzhou Reach of the Yellow River. NPEOs and their metabolites were found in the river, with the maximum dissolved concentrations of 6.38 nmol/L for NPEOs, 0.19 nmol/L for nonylphenol ethoxy acetic acids (NPECs) and 0.79 nmol/L for NP, respectively. The maximum concentrations in the sediment and suspended particle samples were 1.50 and 5.09 nmol/g for NPEOs and NP, respectively. The effects of particles, light and microorganism on the dissipation of NPEOs in the river water were investigated based on lab-scale experiments. When natural particles were removed, 72% and 22% degradation of NPEOs were achieved at 120 h in non-sterile and sterile conditions with light, respectively. Different concentrations of NPECs were also observed in these experiments. When suspended particle matters (SPMs) were present, about 38–50% of NPEOs were sorbed to the particulate phase in only 1 h. As a result, the degradation of NPEOs and production of NPECs were inhibited. However, the combined sorption and degradation in the presence of SPMs resulted in lower dissolved NPEO concentrations than those in the absence of SPMs. Biodegradation was the most important pathway for NPEOs degradation in the river water, while NPECs seemed to be produced through both biological and abiological pathways. [Copyright &y& Elsevier]

• A MoS 2 /rGO heterojunction is introduced to a graphite felt electrode. • The electrode utilizes both dissolved O 2 and gaseous O 2 in 2e− ORR. • The MoS 2 /rGO heterojunction is a nanoscale p-n junction. • Gaseous O 2 adsorbing onto sulfur vacancies is reduced by electrons from rGO. • OH generated by autocatalysis of HAFA promotes As(III) and Cr(III)oxidization. Accumulation of high-arsenic fly ash (HAFA) poses a serious environmental threat due to the toxicity of As and release of other heavy metals especially Cr. In this work, a novel graphite felt (GF) cathode modified with the nanoscale MoS 2 /reduced graphene oxide (rGO) heterojunction is prepared by blending with PTFE emulsion for efficient synergistic oxidative dissolution of As(III) and Cr(III) in HAFA. By taking advantage of the p-n junction characteristics of the heterojunction and appropriate hydrophobicity of the PTFE coating, the modified GF efficiently utilizes both dissolved O 2 and gaseous O 2 in the 2e− oxygen reduction reaction (ORR). Our theoretical assessment indicates that gaseous O 2 adsorbs stably on sulfur vacancies and is reduced by electrons transmitted from rGO. Experimentally, the modified GF shows superior ORR catalytic activity as exemplified by a high peak current density of 8.41 mA cm−2 and onset potential of 0.53 V vs. RHE. OH generated by the Cr and Fe-triggered autocatalysis mechanism promotes oxidization of As(III) and Cr(III) in detoxification of HAFA resulting in 96.1% As removal as well as 70.74% Cr removal in 135 min. The modified GF with excellent stability and durability has immense industrial prospect in detoxification of HAFA and treatment of other types of As-containing hazardous wastes. [ABSTRACT FROM AUTHOR]

Quartz and clay are substituted gradually by fly ash using a triaxial ceramic formulation under simulated industrial conditions and the effects of fly ash substitution on the macroscopic properties and microstructures of the sintered ceramics are evaluated systematically. With the substitution of 35 wt% (1250 °C), the ceramic sample exhibited optimal properties, including linear shrinkage of 15.61%, bulk density of 2.39 g cm-3, water absorption of 0.62% and flexural strength of 41.70 MPa, due to the accelerated densification and fly ash-spurred needle-shaped mullite. The microstructure analysis shows that the sintered matrix consists of three types of particles, quartz-, clay- and feldspar-like particles showing sintering behavior with respect to filling the glassy matrix with preserved morphology, precipitating mullite crystals, and fusing with the surrounding glassy matrix, respectively. The strength of the fly ash - containing ceramics is analyzed by the dispersion-strengthening mechanism and porosity and the results indicate that the fly ash particles affect the mechanical strength due to Griffith flaws when the total porosity is less than 25% and pores at higher total porosity. This study provides a viable strategy to recycle industrial fly ash in the production of architectural ceramics. [Display omitted] • Quartz and clay are substituted by fly ash in a triaxial ceramic formulation. • The ceramic preparation is under simulated industrial conditions. • The substitution effects on macro-properties and microstructures are evaluated. • Three types of particles exist acting as quartz, clay, and feldspar, respectively. • The strength is analyzed by the dispersion strengthening mechanism and porosity. [ABSTRACT FROM AUTHOR]

Although HBr promotes Hg 0 oxidation over the V 2 O 5 -WO 3 /TiO 2 catalyst, it possibly influences the catalyst DeNO x activity. NH 3 -SCR experiments were conducted over a commercial V 2 O 5 -WO 3 /TiO 2 catalyst in the presence of HBr. NO conversion obviously decreases in the low temperature range (i.e., < 300 °C). XPS analysis suggests that HBr reacted with the surface vanadium species, increasing the amount of Br species and V 4 + species. In-situ FTIR study reveals that HBr adsorbed on the catalyst surface and subsequently reacted with V = O species which served as active sites in the SCR reaction, thus resulting in the inhibition effect for the DeNO x activity. [ABSTRACT FROM AUTHOR]

[Display omitted] • Nanoplastics result in significant hepatic immune toxicity in zebrafish larvae. • Nanoplastic accumulation contributes to the ROS generation and the immunotoxicity. • Nanoplastics activate steroid hormone biosynthesis. • Immune transgenic zebrafish is sensitive to the immunotoxicity of nanoplastics. Nanoplastics in aquatic environments may induce adverse immunotoxicity effects in fish. However, there is insufficient evidence on the visible immunotoxicity endpoints in the larval stages of fish. The liver plays an important role in systemic and local innate immunity in the fish. In this study, the hepatic inflammatory effects of polystyrene (PS) nanoplastic particles (NPs: 100 and 50 nm) and micron PS particles on transgenic zebrafish (Danio rerio) larvae were estimated using fluorescent-labeled neutrophils, macrophages, and liver-type inflammatory binding protein (fabp10a). Particles with smaller size induced higher aggregations of neutrophils and apoptosis of macrophages in the abdomen of the larvae, corresponding to greater hepatic inflammation in the larvae. NPs increased the expression of fabp10a in the larval livers in a dose- and size-dependent manner. PS particles of 50 nm at a concentration of 0.1 mg·L−1 increased the expression of fabp10a in the larval liver by 21.90% (P < 0.05). The plausible mechanisms of these effects depend on their distribution and the generation of reactive oxygen species in the larvae. Metabonomic analysis revealed that the metabolic pathways of catabolic processes, amino acids, and purines were highly promoted by NPs, compared to micron PS particles. NPs also activate steroid hormone biosynthesis in zebrafish larvae, which may lead to the occurrence of immune-related diseases. For the first time, the liver was identified as the target organ for the immunotoxicity effects of NPs in the larval stage of fish. [ABSTRACT FROM AUTHOR]

Lytic polysaccharide monooxygenases (LPMOs) can improve the effectiveness with which agricultural waste is utilized. This study described the potent AA9 family protein Ms LPMO3, derived from Morchella sextelata. It exhibited strong binding to phosphoric acid swollen cellulose (PASC), and had the considerable binding ability to Cu2+ with a K d value of 2.70 μM by isothermal titration calorimetry (ITC). Ms LPMO3 could also act on PASC at the C1 carbon via MALDI-TOF-MS results. Moreover, Ms LPMO3 could boost the hydrolysis efficiency of corncob and wheat bran in combination with glycoside hydrolases. Ms LPMO3 also exhibited strong oxidizing ability for 2,6-dimethoxyphenol (2,6-DMP), achieving the best V max value of 443.36 U·g−1 for pH 7.4 with a H 2 O 2 concentration of 300 µM. The structure of Ms LPMO3 was obtained using AlphaFold2, and the molecular docking results elucidated the specific interactions and key residues involved in the recognition process between Ms LPMO3 and cellulose. Altogether, this study expands the knowledge of AA9 family proteins in cellulose degradation, providing valuable insights into the mechanisms of synergistic degradation of lignocellulose with cellulases. • Ms LPMO3 was a novel AA9 family protein and could tightly bind with copper ions. • Ms LPMO3 possessed strong oxidizing ability for 2, 6-DMP. • Ms LPMO3 could oxidize PASC at the C1 site. • Ms LPMO3 exhibited synergistic effects on natural substrates with glycoside hydrolase. [ABSTRACT FROM AUTHOR]

The direct preparation of LiNi 0.8 Co 0.1 Mn 0.1 O 2 (LNCM811) cathode materials from the hydrochloric acid leaching of laterite are promising; however, there are Cl− ions and other impurities in the hydrochloric acid leaching solution, thereby limiting the commercial application of LNCM811. In this study, we compared the LNCM811 prepared from Cl−- and SO 4 2−- ion precursor solutions, and observed that the existence of Cl− ions could result in agglomerate disjointed and the primary particles grew separately during the sintering process, further deteriorating the electrochemical performance. Therefore, the initial raw Ni/Co solid residues were washed with deionised water and leached with 25 wt% H 2 SO 4 solution to obtain an enriched Ni/Co solution with SO 4 2− anions. Furthermore, considerable impurities in the enriched Ni/Co solution caused primary particle separation during the sintering process and led to the LNCM811 having poor electrochemical properties. Therefore, it was further purified by extraction with Cyanex272 to obtain a pure NiSO 4 solution. The impurities in the NCM811 precursor prepared from this pure NiSO 4 solution were below standard limits, the corresponding lithiated cathode delivers an initial reversible capacity of 192.1 mAh g−1 at 0.1C with an initial Coulombic efficiency of 86.5%; it retains 85.1% of its capacity after 100 cycles at 1.0C in 2.8–4.3 V, thereby achieving the standard of commercial LNCM811. On this basis, combined with the previous research of our group, high-value utilisation of laterite for preparing cathode materials includes the following processes: hydrochloric acid leaching, preliminary purification, alkaline oxidation precipitation, conversion of the Cl− solution system to the SO 4 2− ion solution system, extraction, solution-phase synthesis, and calcination. Moreover, compared with the conventional process of preparing NCM811 from metal sulfates, the cost saving through the proposed process was found to be approximately 265.8 $/ton. • Cl− ions result in disjointed agglomeration of LiNi 0.8 Co 0.1 Mn 0.1 O 2. • Mg could lead to poor particle morphology and layered structure. • Extracting impurities via Cyanex272 shortened the production of pure NiSO 4 solution. • LiNi 0.8 Co 0.1 Mn 0.1 O 2 was synthesised from hydrochloric acid leaching of laterite. [ABSTRACT FROM AUTHOR]