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Incorporation of additives into silicon carbide (SiC) ceramics in low temperature, atmospheric pressure sintering is challenging because uniform mixing of additives and raw SiC powders is quite difficult. Herein, an impregnation coating process in which a precise amount of Al 2 O 3 is introduced to raw SiC granules on the nanoscale is described and high-performance SiC ceramics can be processed by atmospheric pressure sintering. The uniform coating promotes densification of SiC via enhanced liquid mass transfer and inhibits grain growth and recombination during sintering. The effects of the doping content on the ceramic structure and mechanical properties are studied. Coating a single layer of Al 2 O 3 nano-particles on SiC particles yield the best interfacial activity, sintering density, and mechanical properties. The SiC sample with 7.5 wt% Al 2 O 3 possesses the best properties such as a relative density of 97.98%, flexural strength of 434.40 MPa, fracture toughness of 5.23 MPa·m1/2, and Vickers hardness of 28.21 GPa. The sintering kinetics analyzed by the isothermal sintering method fits the Singh model with an apparent activation energy of 574.64 kJ/mol. The sintering rate is governed by both the interface reaction and diffusion and the model and experimental results provide insights with respect to materials design and commercial batch production. Unlabelled Image • A facile Al 2 O 3 coating technique for SiC powders is described. • Raw SiC granules are evenly coated with a precise amount of Al 2 O 3 on the nanoscale. • High-quality SiC ceramic samples are prepared by atmospheric pressure sintering. • The sintering kinetics is analyzed by the isothermal method. • The sintering rate is determined by the interface reaction and diffusion. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Low-temperature sintering properties and mechanism of BCTZY NFs were clarified. • BCTZY NFs displayed a high T C owing to its discontinuous physical property. • Vertical alignment and donor doping of Y3+ greatly enhanced electrical properties. • BCTZY NF-based NGs showed great potential in tiny energy harvesting application. Abstract Flexible lead-free (Ba 0.85 Ca 0.15)(Ti 0.9 Zr 0.1)O 3 -0.2 mol%Y nanofibers (BCTZY NFs) were synthesized by electrospinning and their corresponding nanogenerators (NGs) with vertical alignments were fabricated. The low-temperature sintering properties of BCTZY NFs were investigated, to optimize their synthesis path and minimize the thermal energy consumption during the sintering process. The continuity, flexibility, and stability of the BCTZ-based NFs were improved by adding Y3+. Moreover, the temperature-evolved Raman spectra displayed a high Curie temperature of 280 °C for BCTZY NFs, which was far higher than that of about 90 °C for BCTZ-based ceramic bulks, owing to the discontinuous physical property of NFs. The dielectric, ferroelectric, and piezoelectric properties of the vertically aligned BCTZY NFs/PDMS were estimated and compared with those of BCTZ NFs/PDMS composites, to verify the advantages of vertical alignments and the donor doping effect of Y3+. Vertically aligned BCTZY NF-based NGs showed an average V OC of 3.0 V and I SC of 85 nA by finger tapping, suggesting their potential applications in tiny energy harvesting. [ABSTRACT FROM AUTHOR]

BCZT-CuY/rGO/PDMS composites with excellent elasticity and flexibility, and their nanogenerators (NGs) with favorable electrical properties, were fabricated. The impact of rGO on the dispersion of BCZT-CuY, the mechanical properties of BCZT-CuY/rGO/PDMS, and electrical performance of BCZT-CuY/rGO-based NGs were systematically investigated. The results indicated that the distribution of BCZT-CuY in PDMS with added rGO was much more uniform than that without rGO. Moreover, its elastic modulus and elongation at the break increased to 4.6 MPa and 250%, respectively, with the introduction of rGO. Apart from a high d 33 at the percolation threshold, the average V OC (1.36 V) and I SC (35nA) achieved by finger tapping BCZT-CuY/rGO-based NGs suggested their considerable potential in harvesting tiny energy. [ABSTRACT FROM AUTHOR]

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]

• Three shrinking cylinder models are proposed. • The new models are suitable for materials with a high aspect ratio. • Some suggestions to the kinetic analysis in uncatalyzed reactions are provided. The shrinking unreacted core model has been one of the most widely used models for the uncatalyzed reaction kinetics between the liquid/gas and the solid phases. However, the classical shrinking unreacted core model (CSUC model) is only applicable to spherical particles. Currently, the CSUC model has been used in many studies regardless of its applicable conditions. For example, Wang et al. (2016) investigated the decomposition kinetics of a rod-like residue and deduced the rate-controlling step using the CSUC model. The purpose of this comment is to propose a modified shrinking unreacted core model (shrinking cylinder model) suitable for materials with a high aspect ratio. The authors hope that this work will be helpful for kinetic analysis of rod-shaped and fiber-shaped materials in the uncatalyzed liquid/gas-solid reactions. [ABSTRACT FROM AUTHOR]

• 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]

Li- and Mn-rich materials have high capacities but serious voltage attenuation, whereas Ni-rich materials LiNi 0.8 Co 0.1 Mn 0.1 O 2 (NCM) have good rate characteristics but poor stabilities, and they readily to oxidize organic electrolytes. The core–shell strategy with Ni-rich materials as the core and Li- and Mn-rich materials as the shell was expected to balance these merits and drawbacks. In this work, simple and concentration-gradient Li- and Mn-rich shell were successfully synthesized on NCM and critically compared. As expected, a distinct core–shell interface was observed for the simple core–shell cathode, which causes the shell to crack during cycling and exhibits worse electrochemical performance than the single Li- and Mn-rich cathodes and Ni-rich cathodes. In contrast, the fabricated concentration-gradient core–shell cathode shows the uniform fusion of the core and shell at the atomic level, and the overall electrochemical performance is far superior to that of the simple core–shell and pristine cathodes. In addition, it delivers an initial reversible capacity of 226.6 mAh g−1 at a C-rate of 0.1C and 120.2 mAh g−1 at 10.0C, and it retains 86.9% of its capacity after 100 cycles to 4.6 V at 1.0C. Differential capacity versus potential (d Q /d V versus V) and EIS analyses show that the concentration-gradient core–shell cathode has a stable impedance and very stable average voltage. Obviously, the concentration-gradient coating of the Li- and Mn-rich shell can maximize the merits of the core and shell. • Both simple and concentration gradient Li- and Mn-rich shell coated samples increase the capacity of LiNi 0.8 Mn 0.1 Co 0.1 O 2. • A distinct core-shell interface was observed in simple core-shell cathode. • Simple core-shell structure exhibits a negative effect on cycling stability, rate capability and Li-ion diffusivity. • The concentration gradient Li- and Mn-rich shell is able to relieve side reactions and largely improved cycling stability. [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]

We previously established that lentils were able to significantly attenuate the development of hypertension in spontaneously hypertensive rats (SHRs), but the mechanism was not investigated. The current study was therefore designed to examine the effect of lentils on arterial function in relation to arterial stiffness, lipid biochemistry and activation of select aortic proteins. Seventeen-week-old male SHRs were randomly assigned to groups (n=10/group) fed (a) 30% w/w green lentils, (b) 30% red lentils, (c) 30% mixed lentils (red and green) or (d) no lentils for 8 weeks. Normotensive Wistar Kyoto (WKY) groups (n=10/group) received either the mixed lentil or no lentil diet. Blood pressure, pulse wave velocity and serum lipids were measured at baseline and 8 weeks, while pressure myography, arterial morphology and aortic proteins were measured after termination. There were no dietary-related changes in pulse wave velocity or blood pressure for any SHR or WKY group. Low-density lipoprotein cholesterol and high-density lipoprotein cholesterol were significantly lower in only SHR red lentil and WKY mixed lentil groups compared to their controls. The lentil diets reduced the media:lumen ratio of SHRs relative to control-fed SHRs but had no effect on WKYs. Both red and green lentils reduced arterial stiffness of SHRs but not WKYs. SHR lentil groups showed lower aortic p38 mitogen-activated protein kinase (p38MAPK) phosphorylation, thus implying that p38MAPK activation is suppressed with lentil feeding. Lentil-based diets suppress pathological vascular remodeling in SHRs, while green lentils maintain the vascular function of SHRs similar to normotensive WKYs despite the presence of high blood pressure. [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]

Abstract: The effect of sorbed nonylphenol (NP) at low levels on phenanthrene sorption onto the mineral surfaces (organic-removed sediment, kaolinite) and a natural sediment with low organic content was investigated in this study. NP could be sorbed on the sediment and the minerals, and part of sorbed NP interacted with the solid surface stably. At very low concentrations, sorbed NP was observed to inhibit the sorption of phenanthrene on the hydrophilic mineral surfaces (organic-removed sediment and kaolinite) based on the change of phenanthrene apparent solid–liquid distribution coefficients. When the amount of sorbed NP increased to higher levels, enhancement of phenanthrene sorption occurred. Similar result was also obtained in isotherm experiments. On the mineral sorbents contacting with 1.0mg/L NP solution previously, the K d values were lower compared with those on the sorbents without sorbed NP. On the sorbents with higher levels of sorbed NP (contacting with 10mg/L NP solution previously), the K d values increased, while the isotherm tended to be more nonlinear. Concentrations of sorbed NP determined its orientation on the surface, which could presumably affect the water film above the sorbents, or contribute more adsorption sites for phenanthrene. [Copyright &y& Elsevier]

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]

Iron and steel production is one of the most significant anthropogenic sources of atmospheric mercury emission. However, there is little information about this source in China. In this study, we focused on three typical Chinese sintering furnace processes. Mercury in flue gas was sampled using the EPA Method 30B and Ontario Hydro Method, and solid samples were also analyzed. We found that 1.12–4.66% of mercury input in sintering furnace processes was emitted into the atmosphere. The total mercury concentrations in the sintering furnace flue gas were 17.773, 31.765 and 18.275 μg/m 3 ; the major mercury species was oxidized form, which accounted for 73.4– 94.7% of the total mercury. The mercury concentrations in the stack flue gas were 0.373, 0.533 and 0.465 μg/m 3 , while its removal efficiencies by air pollution control devices (APCDs) were 97.5%, 81.1% and 96.8%, and its emission factors were 2.49, 2.71 and 1.28 mg/t sinter. The main mercury inputs were iron ore, coal, coke and lime, where the iron ore input was 74.84– 92.22% of the total mercury quantity. Moreover, mercury was distributed in fly ash (19.22– 81.54%), gypsum (13.29– 46.00%), iron ore sinter (0– 11.45%), and flue gas (1.12– 4.66%). An approximate mercury mass balance could be obtained from various samples in this study. [ABSTRACT FROM AUTHOR]

Dietary conjugated linoleic acid (CLA) reduces indicators of early renal disease progression and the associated elevated cyclooxygenase (COX) levels in young obese rats with obesity-associated nephropathy (OAN). Therefore, renal function and injury and COX and its metabolites were assessed in obese fa/fa Zucker rats with more advanced renal disease. Obese rats at 16 weeks of age were provided with either cis (c)9, trans (t)11 ( fa/fa -9,11) or t10,c12 ( fa/fa -10,12) CLA for 8 weeks, and compared to lean (lean-CTL) and obese ( fa/fa -CTL) rats provided the control diet without CLA. Obese rats displayed significantly reduced renal function and increased renal injury compared to lean rats. In the obese rat groups, glomerular hypertrophy was reduced in both CLA-supplemented groups. While all other measures of renal function or injury were not different in fa/fa -9,11 compared to fa/fa -CTL rats, the fa/fa -10,12 rats had greater renal hypertrophy, glomerular fibrosis, fibrosis, tubular casts and macrophage infiltration compared to the fa/fa -CTL and fa/fa -9,11 groups. The fa/fa -10,12 group also had elevated levels of renal COX1, which was associated with increased levels of two oxylipins produced by this enzyme, 6-keto-prostaglandin F 1α , and thromboxane B 2 . Renal linoleic acid and its lipoxygenase products also were lower in obese compared to lean rats, but CLA supplementation had no effect on these or any other lipoxygenase oxylipins. In summary, supplementation with c9,t11 CLA did not improve more advanced OAN and t10,c12 CLA worsened the renal pathology. Altered production of select COX1 derived oxylipins was associated with the detrimental effect of the t10,c12 isomer. [ABSTRACT FROM AUTHOR]