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• For its high mechanical strength, TiO 2 selected to support CuO oxygen carrier. • Various MgO ratios added to CuO/TiO 2 to enhance its poor anti-sintering. • Oxygen carriers characterization revealed that MgO enhanced anti-sintering. • Fixed bed and TGA used to investigate the oxygen uncoupling reactivity. • High MgO ratios have stable reactivity, high TiO 2 was better first but declined. Copper-based oxygen carrier is a strong candidate for commercial-scale chemical looping technology due to its high reactivity. In contrast, it has poor attrition and sintering resistance. Several supports have been used so far; however, they suffered from a high attrition rate under continuous operation. TiO 2 has not been tested under continuous operation due to its poor sintering resistance, although it has the highest crushing strength. The novelty of this study is to use CuO/TiO 2 and look to enhance its anti-sintering by MgO addition. Incipient wet impregnation method was used to synthesize 60 wt%CuO/40 wt%support (support:40 %TiO 2 , 30 %TiO 2 /10 %MgO, 20 %TiO 2 /20 %MgO, 10 %TiO 2 /30 %MgO, and 40 %MgO) calcinated at 890 °C for 7 h. XRD, XPS, SEM, and BET surface area have been used to characterize oxygen carriers. Oxygen uncoupling performance has been tested on a TGA at 920 °C through 10 cycles. The oxygen uncoupling capacity of all samples was around the theoretical value (6%); results also showed better uncoupling reactivity with a higher load of TiO 2 , while the sintering was also higher, as disclosed by SEM and BET. A fixed bed system was used for additional investigation; its results were almost identical to TGA. The results ascribed to high oxygen vacancies and copper concentration on the surface with a higher load of TiO 2. So, all oxygen carriers have additionally calcinated for 48 h at 920 °C and tested again in a fixed bed, then the effect of sintering was dominant, and the reactivity was uniformly better with a higher load of MgO and sintering resistance. [ABSTRACT FROM AUTHOR]

We present a method for the improvement of the fatigue crack growth (FCG) resistance of a metastable β titanium alloy with uncompromised high strength and ductility by introducing more heterogeneous interfaces produced by diffusion bonding. FCG behavior and tensile properties of this bonded alloy were measured at room temperature. The detailed features of α grains precipitated at the laminated interface and substate during furnace cooling and subsequent aging treatment were characterized. Dense α grains, grain boundary α (α WG) layer-free, and residual stress due to compression strain at the laminated interface can hinder FCG, resulting in an increase of FCG life of 9.4% in the high-layers laminated structure (HLS) sample compared with the low-layers laminated structure (LLS) sample. This available method can be also extended to other near and metastable β titanium alloys as a reference for designing enhanced FCG resistance with uncompromised tensile performance. [Display omitted] [ABSTRACT FROM AUTHOR]

Microstructure evolution and fatigue crack growth (FCG) behaviors of diffusion bonded Ti-6Al-4 V titanium alloy with synchronously changed temperature and pressure are systematically investigated. Ti-6Al-4 V alloy plates can be metallurgically bonded under suitable process parameters. Meanwhile, bonded plates displayed different FCG resistance and excellent tensile properties at room temperature. FCG life of the 780–18 (bonded temperature-pressure) sample from a crack length of 0.5 mm to fracture is 108147 cycles, which is 1.6 and 1.84 times than that of the 830–12 and 900–6 samples, respectively. According to the observation of crack paths and α grain crystallography before and after fatigue tests, fatigue crack propagation is mainly affected by the α crystallographic orientation, α grain size, and β phase. By choosing higher pressure (18 MPa) to promote bonding and lower temperature (780 ºC) to optimize the microstructures, diffusion bonded Ti-6Al-4 V alloy can be achieved outstanding FCG resistance with uncompromised tensile properties in this study. ● Ti-6Al-4 V is diffusion bonded with synchronously changed temperature and pressure. ● Excellent FCG resistance with uncompromised tensile property is obtained. ● { 0001 } 〈 10 1 ¯ 0 〉 texture and fine α grains improve FCG resistance. ● β phase can hinder crack motion and change forward direction. [ABSTRACT FROM AUTHOR]

By adjusting the initial δ-ferrite (δ) microstructure based on the cold-rolling, two types of unusual austenite (γ) transformation were investigated in a medium-Mn steel during intercritical annealing. First, δ/α' (martensite) phase interfaces are considered advantageous nucleation sites for γ transformation. When the cold-rolling reduction ratio reaches up to 70% (CR70 sample), δ phase morphology evolves from fibrous structure to small pieces, resulting in more δ/α' (martensite) phase interfaces. The results reveal that an increase in δ/α' phase interfaces promotes γ formation ranging from 15.7% to 17.9% (in volume fraction) for samples subjected to quenching and annealing. Furthermore, the γ nuclei are found to grow into both phases, accompanied by a gradual shrinking of local α' and δ phases due to γ transformation. Secondly, precipitation of carbide particles from δ phase in cold-rolled samples also creates a condition for subsequent γ nucleation within δ grains, and then the dissolution of the carbides accelerates γ development. Besides, the thin piece structure of δ phase in the CR70 sample can transform into γ phase at an elevated degree of austenitization. This study innovatively sheds light on the effect of δ phase on γ transformation in medium-Mn steels. [ABSTRACT FROM AUTHOR]

• Sound joint and fine equiaxed α grains reduce FCG rate with good tensile property. • β phase can hinder crack motion and change forward direction. • TA15 alloy with random orientation of α grains exhibits higher FCG resistance. • Local α grains with high Schmid factors are activated to plastically deform. Fatigue crack growth behavior of TA15/TC4 dissimilar laminates produced by diffusion bonding is studied. A sound bonding interface and fine equiaxed microstructure are obtained to improve fatigue damage tolerance with uncompromised tensile properties. TA15 alloy in the dissimilar laminates exhibits a higher fatigue crack growth resistance. EBSD analysis confirms that more α recrystallization occurs in TA15 alloy, which contributes to the relatively random crystallographic orientation and therefore the lower crack propagation rate. Local α grains characterized by high basal or prismatic Schmid factors are activated for plastic deformation accompanied by observation of dislocation lines and tangles. This study sheds light on a simple method to improve the damage tolerance by fabricated dissimilar laminate of diffusion bonding. [ABSTRACT FROM AUTHOR]

• The enhanced soot oxidation activity is ascribed to the formation of surface oxygen vacancies. • The low initial temperature (T ig = 308 °C) and the low temperature of maximum CO 2 emission (T max = 389 °C) were achieved. • DFT calculations were performed to correlate with the activity test results. Soot particle exhausted from diesel engines are causing severe health and environmental problems. Alkali metals (Li, Na, K, Cs) doped CuFe 2 O 4 catalysts were synthesized to eliminate soot residue. XRD, Raman, SEM, H 2 -TPR and temperature-programmed oxidation (TPO) were employed to investigate the effect of alkali metals addition on CuFe 2 O 4. Density functional theory (DFT) calculations were used to explore the inner reaction mechanism. The results revealed that the doping of all alkali metals facilitated the formation of oxygen vacancies which are the main active sites for soot oxidation. The CuFe 2 O 4 doped by K showed smallest crystal size and the most oxygen vacancies. Therefore, Cu 0.9 K 0.1 Fe 2 O 4 catalyst performed best catalytic activity in soot oxidation with the T ig of 308 °C and T max of 389 °C. [ABSTRACT FROM AUTHOR]

A method was proposed to improve the fatigue crack growth (FCG) resistance of TC4 (Ti6Al4V) titanium alloy laminate by hydrogenation/low-temperature diffusion bonding/dehydrogenation (H-DB-DH) combined process. Effects of hydrogen contents and different dehydrogenation temperatures on FCG behaviors and tensile properties as well as microstructures were investigated. Residual hydrogen contents beneath fatigue fracture surfaces were measured to determine the safe dehydrogenation temperature. The hydrogen content of 0.3 wt% and dehydrogenation temperature of 780 °C are optimal to produce TC4 laminate with a 9.87 % improvement of FCG life compared with the diffusion bonded one without hydrogenation. FCG rate decrease results from the comprehensive effect of recrystallization volume fraction increase, grain refinement, mean geometrically necessary dislocations (GNDs) density decrease and texture intensity weakness as well as texture diversity improvement. This paper provides theoretical support for fatigue property improvement of titanium alloy by hydrogen diffusion bonding process. • FCG life increases by 9.87 % by using H-DB-DH combined process. • The optimal dehydrogenation temperature and the safe hydrogen content range are obtained. • FCG rate decrease results from comprehensive mechanisms. • Intragranular crack deflection in α p grains makes fatigue crack path tortuous. [ABSTRACT FROM AUTHOR]

Shunhao Zhang and Tianle Li contributed equally to this work Correction to: Microb Cell Fact (2021) 20:108 https://doi.org/10.1186/s12934-021-01599-y Following publication of the original article [[1]], the authors identified a problem with the authorship. The authorship has been updated in the original article and the correct authorship may be seen in this correction. However, as Shunhao Zhang and Tianle Li contributed equally to this work, Tianle Li should in fact be regarded as a co-first author. [Extracted from the article]

• Properties and catalytic mechanism of molten alkali carbonate (MAC) are presented. • Adding MAC for coal and biomass gasification over CO 2 enhanced CO production. • MAC catalyst reduced reaction temperature, activation energy, and tar. • Coal reactivity enhances by AAEMs exist in biomass ash during co-gasification. • Existent of Si/Al inhabit co-gasification due to alkali aluminosilicates formation. Carbon gasification in molten alkali carbonate salts over CO 2 is a process to produce gaseous fuels with mitigating the greenhouse effect. Alkali carbonate salts can facilitate Boudouard reaction, which is difficult to occur even at high reaction temperature if the catalyst is absent. Alkali carbonate allows easily carbon−CO 2 contact by changing the reaction interface from gas-solid to gas-liquid. This review focused on CO 2 utilization for alkali carbonate gasification and biomass/coal co-gasification. CO 2 gasification of biomass and coal with the alkali carbonate salts enhances the carbon conversion rate and CO yield. Furthermore, alkali carbonate salts gasification of biomass and coal could reduce reaction temperature, activation energy, and tar formation in the product gas. The factors that influence the carbon conversion rate were discussed, such as reaction temperature, CO 2 concentration, alkali carbonate addition, and char feeding mode. On the other hand, blending coal with biomass is considered as potential fuel base for CO 2 co-gasification and displays an advantage for improving the coal char reactivity. The alkali and alkaline earth metals (AAEMs) present in biomass ash acted as a natural catalyst to increase the coal reactivity and CO production. The catalytic effect in the co-gasification enhances by raising the percentage of biomass in the blend. In contrast, the inhibiting effect in co-gasification could be attributed to silica and alumina reactions with AAEMs to form aluminosilicates complexes. [ABSTRACT FROM AUTHOR]

• The solid-solid reaction mechanism of CuFe 2 O 4 with C was studied both experimentally and theoretically. • Oxygen ion migration in CuFe 2 O 4 promotes the solid-solid reaction. • DFT results showed that C atom was in favor of adsorbing on O-terminated surface of CuFe 2 O 4. Oxygen carriers are critical in chemical-looping system to transfer oxygen and heat. Spinel CuFe 2 O 4 is a promising oxygen carrier due to its low decomposition temperature, good resistance to sintering and oxygen deficiency. In this study, a comprehensive investigation of solid-solid reaction of CuFe 2 O 4 with C was conducted on a fixed-bed reactor. The XRD, Raman and SEM proved the primary structure of CuFe 2 O 4 with uniform external morphology in size and shape. The weight loss of CuFe 2 O 4 in TG showed that it could release O 2 at about 700 °C. The XRD and Raman results of solid products for various time intervals showed that CuFe 2 O 4 was mainly transformed into CuFeO 2 and Fe 3 O 4 with a rapid reaction rate at the initial stage, and then CuFeO 2 was reduced to Cu and Fe 3 O 4 , Fe 3 O 4 was slowly reduced to FeO eventually. The DFT results indicated that C was in favor of adsorbing on O-terminated surface, and CuFe 2 O 4 transformed into CuFeO 2 and Fe 3 O 4 accompanied by the formation of CO x. [ABSTRACT FROM AUTHOR]

To enhance the thermal stability, electrochemical compatibility, and overshoot protection of separators, it is common practice to incorporate inorganic particles for separator modification. In this work, we discussed a polypropylene (PP) separator that was coated with a combination of hydrothermal boehmite (AlOOH) and ammonium polyphosphate (APP). The coating layer can greatly reduce the thermal shrinkage rate of the separator, enabling the modified separator to retain its original size at 180 °C. In addition, part of the material formed by the decomposition of the coating material at high temperatures can be well-diluted oxygen, thus reducing the risk of combustion. Furthermore, the presence of the coating layer increases the ionic conductivity and electrolyte wettability, thereby improving the cycle stability of the battery. This study utilizes inexpensive, lightweight, and eco-friendly materials to enhance a commercially available polypropylene separator. This modification not only increases the efficiency of material usage but also enhances the economic and environmental advantages of the improved separator. [Display omitted] [ABSTRACT FROM AUTHOR]

CH 3 COOH oxidation is the rate-determining step in the oxidation process of C 2 H 5 OH and CH 3 CHO. The generation of sulfuric acid consumes the active metal component Mn3+/Mn2+ on the Mn-HTLCs surface of Mn-HTLCs, resulting in catalyst deactivation. [Display omitted] • The adsorption strength order was CH 3 CHO-O > C 4 H 10 S-Mn > C 2 H 5 OH-Mg. • Mg–O–H...O-C, O...O=C, and Mn–O–H...S–C promoted the adsorption process. • Mn3+/Mn2+ and oxygen defects contribute to the active sites. • CH 3 COOH oxidation determines the oxidation process of C 2 H 5 OH and CH 3 CHO. • Free O atoms, O 2, and ·HO 2 promote the oxidation removal of VOCs. The biological fermentation industry faces a challenge in simultaneously purifying complex sulfur-containing volatile organic compounds (VOCs) and reducing tail gas emissions. This is due to the multi-step purification process required for sulfur-containing VOCs and the high energy usage involved. The adsorption performance and controllability of elements in hydrotalcite-like compounds are noteworthy and have the potential to enhance the catalytic purification of sulfur-containing VOCs. This study utilizes Mn-based hydrotalcite-like compounds as a highly efficient catalyst for the simultaneous catalytic removal of complex sulfur-containing VOCs such as ethanol (C 2 H 5 OH), acetaldehyde (CH 3 CHO), and diethyl sulfide (C 4 H 10 S). The study successfully achieves the simultaneous and efficient removal of sulfur-containing VOCs at a temperature of 325 °C. The removal rates of three types of gas pollutants can reach 100 % for 420 min, 450 min, and 360 min, respectively. Meanwhile, the VOCs breakthrough capacity is 426 mg/g. The competitive adsorption effect, adsorption sites, and reaction mechanism were investigated using experimental and theoretical calculation methods. The simultaneous adsorption of three gases resulted in competitive adsorption, with the priority order of adsorption being CH 3 CHO > C 4 H 10 S > C 2 H 5 OH. The various adsorption effects were attributed to the formation of Mg–O–H...O-C, O...O=C, and Mn–O–H...S-C, respectively. CH 3 CHO was initially adsorbed at the O-Top site, while C 4 H 10 S was adsorbed at the Mn-Top site. C 2 H 5 OH was adsorbed at the Mg-Top site. High-temperatures promote the oxidation of elemental S to sulfate. The primary reason for catalyst deactivation is the buildup and coating of sulfate on the surface of the catalyst. The main active sites responsible for the catalytic oxidation of C 4 H 10 S were Mn2+ and Mn3+. The oxygen defects act as active sites for the oxidation of C 2 H 5 OH and CH 3 CHO. C 2 H 5 OH undergoes gradual oxidation to form CH 3 CHO and CH 3 COOH (acetic acid), which are further oxidized to CO 2 and H 2 O. C 4 H 10 S was oxidized to elemental S and eventually to sulfate. The experimental results in this work are consistent with the theoretical results, providing a theoretical basis for the simultaneous catalytic removal of sulfur-containing VOCs. [ABSTRACT FROM AUTHOR]

Fe/CeO2 catalysts with different ferrum loading were prepared by solid state melting method. Ethanol decomposition on those catalysts at different temperature (600, 700, and 800°C) has been studied. To evaluate the catalytic performance in ethanol decomposition, gaseous and solid products produced from ethanol decomposition were collected and analyzed; H2 and multi-walled carbon nanotubes (MWCNTs) were obtained. In these experiments, ethanol decomposition on Fe (30 wt%)/CeO2 at 600°C showed the maximum H2 yield (the maximum H2 yield was 94%, which was higher than that of previous reports). In addition, other gaseous products include CH4 and CO were observed, but CO2 was not be detected. The content of H2, CO, and CH4 were 60 ~ 80%, 20 ~ 25%, and 0 ~ 10%, respectively. MWCNTs have formed in ethanol decomposition process, the quality and purity of MWCNTs increase with increasing temperature, and the material with the carbon-encapsulated metal structure was obtained. [ABSTRACT FROM AUTHOR]

• Adjusting OLR alone is not sufficient in designing and operating TH-AD process, NH 4 +-N and VFAs should be equally considered. • NH 4 +-N, VFAs and tCOD in feed sludge were the most influential factors for AD microbial community structure. • Higher diversity of microorganisms and methanogens that adapted to more diverse substrate transformation pathways could lead to superior performance. • Microbial community information could help the precise design and operation of full-scale TH-AD process. Anaerobic digestion (AD) with thermal hydrolysis (TH) pretreatment is a promising process for excess sludge treatment, while there lacks of the knowledge from full-scale process about the impact of sludge composition and characteristics on microbial community and performance. The sludge physiochemical indices, microbial community and performance data of four full-scale TH-AD plants were characterized, and their relationships was elucidated. The four plants were operated under almost similar total organic loading rate (OLR) but their methanogenesis performance differentiate into two groups, namely superior group (SupG) and the inferior group (InfG). In both groups, TH effectively solubilized particulate organic compounds, meanwhile raised the ammonia nitrogen (NH 4 +-N) and volatile fatty acid (VFA) concentration. Compared with the SupG, thermal hydrolyzed sludge of InfG had higher level of VFAs, NH 4 +-N and total chemical oxygen demand (tCOD), which showed higher inhibition effect on microbes, leading to a community with lower diversity, lower abundance of carbohydrate degrading functional guild, higher protein degrading one, and methanogens that adapted to limited substrates, and further declined the methane production rate. Thus, it was recommended that OLR alone was not sufficient for controlling the system in design and operation, the concentration of VFAs, NH 4 +-N and tCOD should be equally considered. Their higher concentration, together with the higher abundance of Defluviitoga and Proteiniphilum were recommended as indicators for inferior running condition. Our results proposed that microbial communities played a role of bridge between environmental factors and performance, provided implications for engineering ecology and operational regulation for full-scale sludge TH-AD process. [Display omitted] [ABSTRACT FROM AUTHOR]

The Catering Service Industry (CSI) experienced profound impacts due to the COVID-19 pandemic. However, the long-term and multi-timepoint analysis using big data remained limited, influencing governmental decision-making. We applied Kernel Density Estimation, Shannon Diversity Index, and the Geographic detector to explore the spatial heterogeneity and determinants of the CSI in Beijing during the pandemic, with monthly granularity. The temporal-spatial dynamics of the CSI presented a "W"-shaped trend from 2018 to 2023, with pivotal shifts aligning with key pandemic stages. Spatial characteristics exhibited heterogeneity, with greater stability in the city center and more pronounced shifts in peripheral urban zones. Districts facing intricate outbreaks showed lower catering income, and Chinese eateries exhibited heightened resilience compared to others. The CSI displayed strong interconnections with living service sectors. Development in each district was influenced by economic level, population distribution, service facilities convenience, and the risk of the COVID-19 pandemic. Dominant factors included total retail sales of consumer goods, permanent population, average Baidu Heat Index, density of transportation and catering service facilities, infection cases and the consecutive days with confirmed cases existing. Consequently, we suggested seizing post-pandemic recovery as an avenue to unlock the CSI's substantial potential, ushering a fresh phase of growth. [ABSTRACT FROM AUTHOR]

Achievement of nitrite accumulation is critical for the application of advanced nitrogen removal processes. Two lab-scale sequencing batch biofilm reactors (SBBRs) and two sequencing batch reactors (SBRs) were operated under intermittent aeration with different feeding patterns. The nitrite accumulation ratio was 56.6% (pulse feeding) and 68.9% (constant feeding) in SBBRs with nitritation. Nitrate accounted for 98% of the effluent nitrogen in SBRs with complete nitrification. The dominant nitrifier was Nitrosomonas in SBBRs and Nitrospira in SBRs. Four types of acyl homoserine lactones (AHLs) were detected. N ‑[(RS)‑3‑Hydroxybutyryl]‑ l ‑homoserine lactone and N ‑octanoyl‑ l ‑homoserine lactone had a high concentration in the extracellular polymeric substance phase, and had an obvious relationship with nitrite accumulation and ammonia removal. Various microbial communities coexisted in nitrifying systems, with diverse microbial interactions. Microorganisms harboring AHLs-related genes had more interactions with each other, suggesting that nitritation could be regulated by AHLs based quorum sensing. Unlabelled Image • Nitritation was achieved in SBBR while complete nitrification in SBRs. • AHLs concentration was correlated with the performance of nitritation. • High concentrations of AHLs were detected in the EPS phase of SBBRs. • Microbial interactions occurred among microorganisms with AHLs-related genes. • Balance between QS and QQ-organisms might regulate nitritation performance. [ABSTRACT FROM AUTHOR]

Abstract Numerous nanomaterials have been utilized for novel biosensors with sensitivity and selectivity in the last decades due to their intrinsic unique properties. Herein, a facile fluorescence method for nucleic acid detection was developed by employing TiO 2 nanowires (NWs) as the sensing platform. The quenching effect of TiO 2 NWs to fluorophore-labelled single-stranded DNA (ssDNA) was found to be more significant than that to fluorophore-labelled double-stranded DNA (dsDNA) or triplex DNA probes. More importantly, the whole quenching process was also fast since it just took about ten minutes to reach the equilibrium. Based on the different affinities of TiO 2 NWs to ssDNA, dsDNA and triplex DNA probes, the sequence-specific nucleic acids were detected with sensitivity and specificity. Further investigation has demonstrated that the quenching efficiency of TiO 2 NWs to long ssDNA was apparently superior than that to short ssDNA. Moreover, the fluorescence from various ssDNA probes labelled with a wide spectrum of fluorescent dyes could also be quenched by TiO 2 NWs. These inspiring results reveal that TiO 2 NWs could be an excellent universal nanoquencher used in the next-generation biosensors. Graphical abstract A facile fluorescence method was developed for sequence-specific single- and double-stranded DNA detection by using TiO 2 nanowires as a nanoquencher. fx1 Highlights • Excellent quenching ability of TiO 2 nanowires to dye-labelled single-stranded DNA probes was demonstrated. • The TiO 2 nanowire-based sensing platform could be used for nucleic acid assay with high sensitivity and selectivity. • The nucleic acid sensing platform based on TiO 2 nanowires was simple and fast. [ABSTRACT FROM AUTHOR]

• Stability and oxygen uncoupling of novel CuO/MgO/TiO 2 oxygen carrier optimized. • Effect of impregnating CuO/TiO 2 prior and then MgO investigated. • Effect of partial replacement of MgO by ZrO 2 studied. • Long-term cycling in a batch fluidized bed and several characterizations used. • Multi-impregnation and ZrO 2 enhanced stability especially attrition resistance. In our ongoing campaign, we are attempting to address the inferior stability of CuO oxygen carrier because it has exceptional reactivity in the chemical looping field ascribed to its oxygen uncoupling feature. In our previous work, impregnation method employed to synthesize CuO on novel double supports with strong anti-sintering (MgO) and high-crushing strength (TiO 2) materials. Outstanding reactivity and sintering resistance were reported over 10 TGA cycles, while TiO 2 recorded a weak XRD peak and Cu 2 MgO 3 formed. This study has investigated impregnating Cu precursor on TiO 2 , followed by impregnating Mg precursor, for further modifications. The effect of partial replacement of MgO by ZrO 2 was also investigated. The stability has been investigated over 21 cycles in a batch fluidized bed and materials characterized by XRD, XRF, SEM-EDS, and XPS techniques. Strong interaction between MgO and TiO 2 has been identified, producing undesired MgTiO 3 and MgTi 2 O 5 ; however, impregnating Cu over TiO 2 first significantly inhibited this phenomenon; recorded better stability. Replacement of MgO by ZrO 2 also remarkably reduced MgO-TiO 2 interaction and showed the highest XRD peak of desired (TiO 2) rutile. SEM proved high sintering resistance for all samples throughout cycling, with slight grain growth. A sample with two impregnation steps and ZrO 2 addition reported the best overall stability and the highest oxygen vacancies (XPS). Cu 2 MgO 3 was detected in all samples, more clearly after cycles; however, it did not detect by XRD of reduced samples, suggesting it dissociates in inert condition and eventually did not reduces oxygen uncoupling capacity. [ABSTRACT FROM AUTHOR]

Aluminum alloy/steel laminated parts can be fabricated by separated sheets based on a friction stir-assisted incremental sheet forming with synchronous bonding (FS-ISF&SB) method. The current work aims to realize comprehensive understanding of microstructure evolution during FS-ISF&SB and its effect on mechanical properties of the formed parts. Three typical sets of experiments with different combinations of process parameters are carried out, and three different regions are classified by grain feature, defined as deformed region, loading region and undeformed region. Recrystallization and recovery behaviors occur at all of the three regions on both sheets, which generate softening effect. However, the effect of work hardening keeps a dominant role on mechanical property compared with softening effect on steel, while the influence level of these effects on aluminum alloy is opposite during FS-ISF&SB. Besides, stratified structure and gradient distribution of grain size from the outer surfaces to the interface are observed. The microstructure evolutions greatly accelerate the atomic diffusion and subsequently promote the metallurgical bonding of the laminates. It is also found that Fe–Al intermetallic compounds (IMCs) consisting of FeAl 3 and Fe 2 Al 5 are generated on the dissimilar interface of the fabricated parts. The thickest IMCs are usually found at the loading regions. Moreover, the maximum nominal bonding stress obtained by peeling test of the laminated parts can reach 100.0 MPa with the moderate thickness of IMCs as of 13.1 μm. • Investigated effect of microstructure evolution on mechanical performance during FS-ISF&SB. • Explored stratified structure and grain gradient distribution through thickness direction. • Revealed recovery & recrystallization behaviors in Al alloy and steel across thickness. • Discussed competing behavior of work hardening and softening effect during FS-ISF&SB. • Revealed atom diffusion bonding mechanism accelerated by recovery and recrystallization. [ABSTRACT FROM AUTHOR]

Lithium-ion (Li-ion) batteries assembled with gel polymer electrolytes (GPEs) are predicted to increase battery energy density while maintaining battery safety. In this work, poly (vinylidene fluoride- co -hexafluoropropylene) (PVDF-HFP) is successfully used as a polymer matrix to prepare a new kind of GPE (PHHNT) by ultraviolet (UV) curing technology. The polymer network structure formed by photopolymerization technology significantly enhances the tensile properties of the electrolyte. Lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) improves the concentration and transport efficiency of lithium ions in the electrolyte as well as the ionic conductivity (1.22 × 10−3 S cm−1) of the GPEs. In addition, the unique tubular structure of the halloysite nanotube (HNT) and the opposite charges carried by the inner and outer surfaces provide additional channels for the lithium salt and facilitate its dissociation. This enhances the expedited movement of Li+ inside the electrolyte, while simultaneously improving the electrochemical and thermal durability of the electrolyte. The assembled LiFePO 4 (LFP)/PHHNT/Li battery has an initial discharge-specific capacity of 140.5 mAhg−1 at a current density of 0.5C, showing a high capacity retention rate of 89 % after 120 cycles. The design of this composite material significantly improves the overall performance of the electrolyte and is more suitable for flexible and safe solid-state Li-ion batteries. [Display omitted] • UV-cured P(BA-co-EGDMA) copolymer enhances the stretchability of the electrolyte. • LiTFSI increases the Li + concentration and transport efficiency in the electrolyte. • HNT with opposite charges provides unique transport pathways for lithium salts. • Thermal stability of the electrolyte is improved. • The growth of lithium dendrites is inhibited. [ABSTRACT FROM AUTHOR]

[Display omitted] • HTCN reacts to form inorganic substances such as Na 3 N at sodium electrode measurement. • Molecular dynamics simulations of the electrolyte were calculated using Materials Studio. • HTCN additives help the SEI layer to be firm and flat, facilitating the battery's reversible cycling. • HTCN additive effectively reduces the growth of sodium dendrites and increases battery safety and stability. • High cycling stability (4500 cycles) was obtained by assembling the NVP/Na full-cell. Sodium-metal batteries (SMBs) offer substantial competitiveness owing to their wide elemental distribution and high specific capacity. However, SMBs face safety issues such as unstable properties of the Solid Electrolyte Interphase (SEI) layer due to irregular sodium dendrites. In this paper, we constructed a stable and uniform SEI layer by introducing the 1,3,6-Hexanetricarbonitrile (HTCN) electrolyte additive, replacing the conventional, insoluble nitrate. HTCN facilitates the generation of substances like Na 3 N with high electrical conductivity on the Na anode surface. This accelerates Na+ shuttling and provides high-flux nucleation sites. Molecular dynamics simulations were employed to elucidate the solvated structure of electrolyte and radial distribution of Na+ after HTCN addition. Moreover, in-situ optical microscopy revealed a stable and robust SEI layer, effectively inhibiting the disorderly growth of sodium dendrites. The superior cycling performance of the Na 3 V 2 (PO 4) 3 (NVP)/Na full cell further demonstrates the addition of HTCN. [ABSTRACT FROM AUTHOR]

• Oxygen uncouples ability of CuO at low temperatures tested by adding AAEMs oxides. • 5% wt of Na 2 O, K 2 O, MgO, and CaO added to CuO. • An isothermal test was done; MgO, CaO enhanced the process and Na 2 O, K 2 O declined. • Kinetic analysis has been conducted for a more in-depth investigation. • Kinetic results was matched with the experimental, in both MgO was the best. Oxygen uncoupling is one of the most valued properties of oxygen carriers in chemical looping field. It allows to combust the fuel without gasification step and significantly enhances reactivity in all chemical looping fuel oxidation technologies (combustion, gasification, and reforming). Furthermore, it progressed recently to produce pure oxygen (Chemical looping air separation). However, few materials have this merit, among which CuO has the highest reactivity and oxygen transport (uncoupling) capacity. However, it needs a high temperature (about 950 °C) for a high effective reaction rate; in contrast, it suffers high attrition rate and sintering about this temperature. This work aimed to test the ability to enhance the uncoupling at lower temperatures by adding a small amount of common alkali and alkaline earth metals (AAEMs) oxides. CuO was prepared with 5%wt of Na 2 O, K 2 O, MgO, and CaO. An isothermal test was conducted in TGA at (850, 890, and 930 °C) to investigate the effect of additions. For deeper investigation, kinetic analysis has been conducted based on isothermal results. The model of reaction inferred was A 2 α of Avrami-Erofeev (g α = - l n 1 - α 1 / 2) for pure CuO and with all additions, and then the activation energies and pre-exponential factors were calculated. Accordingly, CaO addition showed little increase in the reaction rates while the effect of MgO was significant. In contrast, Na 2 O and K 2 O addition declined the uncoupling rate. [ABSTRACT FROM AUTHOR]

The development of cost-effective electrocatalysts for efficient hydrogen evolution reaction (HER) is of paramount significant for future renewable energy. Pt-based catalysts have been recognized as the most effective electrocatalysts for HER. Developing low-cost and excellent electrocatalysts is a crucial step to achieve its commercial application, because of its high cost and scarcity. In this study, we fabricate carbon encapsulated Ni nanoparticles (NPs) and low Pt NPs supported on carbon nanotubes (CNTs). These samples are synthesized through catalytic decomposition of methane on Ni/CNT catalyst, and Ni/CNT is prepared using the polyol reduction method. Ni@C and Pt are uniformly dispersed on the CNTs. Ni@C-10 with low Pt loading (0.49wt%) exhibits superior HER activity and excellent stability even higher than that of commercial 20wt% Pt/C. Ni@C-10 (Pt loading is 4.3 µg cm−2 on the working electrode) exhibits negligible onset potential, and only 40 mV vs RHE potential is required to support 10 mA cm−2 in 0.1 M H 2 SO 4 aqueous solution, which is better than 19 mV of Pt/C (59 mV). It achieve a low Tafel slope of 31.7 mV dec−1 close to Pt/C (29.3 mV dec−1). After 2000 cycles, it exhibits negligible potential shift (1 mV). This study provides an avenue for developing the efficient catalysts for HER with low Pt loading. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the effects of exercise on muscle fiber conversion, muscle development and meat quality in the biceps femoris (BF) muscle of Sunit sheep. Twelve Sunit sheep with similar body weight were divided into two groups: control group (C group) and exercise group (E group), E group lambs underwent 6 km of exercise training per day for 90 d. The findings revealed that compared with the C group, exercise training enhanced the expression of MyHC IIa mRNA, decreased the number ratio of type IIB muscle fibers and the expression of MyHC IIb mRNA (P < 0.05). Furthermore, the E group lamb displayed higher creatine kinase (CK) activity, and lactic acid levels (P < 0.05), while glycogen content and lactic dehydrogenase (LDH) activity showed opposite trends (P < 0.05). Exercise significantly up-regulated the mRNA expression of AMP-activated protein kinase α1 (AMPKα1), sirtuin1 (SIRT1), peroxisome proliferator-activated receptor gamma coactivator 1-α (PGC-1α), cytochrome c oxidase IV (COX IV), protein kinase B (Akt), mammalian target of rapamycin (mTOR) and p70 Ribosomal S6 Kinase 1 (p70s6k1) (P < 0.05), suggesting exercise promoted muscle fiber conversion by mediating AMPK/PGC-1α pathway, and improved skeletal muscle development via Akt/mTOR pathway. Besides, backfat thickness and pH 45min value in the E group decreased significantly, while the pH 24 , a* , and shear force value increased significantly (P < 0.05). To conclude, this study suggested that exercise training can be used to alter muscle fiber characteristics and muscle development in lamb production. [Display omitted] • Exercise training triggered switch in muscle fiber type. • Exercise training promoted skeletal muscle development. • Exercise training increased shear force and improved meat color in lamb. [ABSTRACT FROM AUTHOR]

• The ion behavior of Na+ and Li+ is explained in terms of activation energy of chemical reaction and Gibbs free energy. • A layered sodium transition metal oxide electrode with ordered mixing of Na/Li ions was prepared by ion exchange method. • The priorities of Na+ and Li+ deblock reactions are is determined by thermodynamic analysis and material characterization. • The competition mechanism of alkali metal ions and the double gain effect of Li are revealed by electrochemical experiments. Dual alkali metal ion battery is expected to apply in future high-efficiency energy storage applications as it can skillfully combine the advantages of Li+ and Na+. However, the specific insertion and extraction processes of the two ions are not well explained. Herein, a layered sodium transition metal oxide electrode with ordered mixing of Na/Li ions is prepared by ion exchange method. The ion behavior is explained in terms of activation energy of chemical reaction and Gibbs free energy. Based on thermodynamic analysis and material characterizations, the priorities of Na+ and Li+ deblock reactions are determined. The competition mechanism of alkali metal ions and the double gain effect of Li are revealed by electrochemical experiments. This work is expected to provide a positive impact on the future design of multifunctional cathodes for advanced rechargeable batteries. [ABSTRACT FROM AUTHOR]

[Display omitted] • EWFED achieves risk warning based on the empirical cumulative distribution function. • EWFED designs a food safety risk classification method based on the "3 σ rule". • An explainable unsupervised risk early warning framework applied to food safety. Efficient food safety risk assessment significantly affects food safety supervision. However, food detection data of different types and batches show different feature distributions, resulting in unstable detection results of most risk assessment models, lack of interpretability of risk classification, and insufficient risk traceability. This study aims to explore an efficient food safety risk assessment model that takes into account robustness, interpretability and traceability. Therefore, the E xplainable unsupervised risk W arning F ramework based on the E mpirical cumulative D istribution function (EWFED) was proposed. Firstly, the detection data's underlying distribution is estimated as non-parametric by calculating each testing indicator's empirical cumulative distribution. Next, the tail probabilities of each testing indicator are estimated based on these distributions and summarized to obtain the sample risk value. Finally, the "3 σ Rule" is used to achieve explainable risk classification of qualified samples, and the reasons for unqualified samples are tracked according to the risk score of each testing indicator. The experiments of the EWFED model on two types of dairy product detection data in actual application scenarios have verified its effectiveness, achieving interpretable risk division and risk tracing of unqualified samples. Therefore, this study provides a more robust and systematic food safety risk assessment method to promote precise management and control of food safety risks effectively. [ABSTRACT FROM AUTHOR]

[Display omitted] • Spring poses the highest ARG abundance and risk in full-scale AD plant. • Risk scores are not always lower after AD due to the increased Rank I ARG ratio. • Dynamics of ARGs is much more chaotic (nonlinear) than microbial community. • EDM exhibits good potential in predicting the dynamics of ARGs and microbes. The long-term occurrence, dynamics and risk of antibiotic resistance genes (ARGs) in anaerobic digestion (AD) of excess sludge (ES) are not fully understood. Therefore, 13-month metagenomic monitoring was carried out in a full-scale AD plant. The highest ARG abundance and risk scores were observed in spring. AD achieved a 35 % removal rate for the total ARG abundance, but the risk score of AD sludge was not always lower than ES samples, because of the higher proportion of Rank I ARGs in AD sludge. ARGs showed less obvious patterns under linear models compared with microbial community, implying their chaotic dynamics, which was further confirmed by nonlinearity tests. Empirical dynamic modeling performed better than the autoregressive integrated moving average model for ARG dynamics, especially for those with simple and nonlinear dynamics. This study highlighted spring for its higher ARG abundance and risk, and recommended nonlinear models for revealing the dynamics of ARGs. [ABSTRACT FROM AUTHOR]

Ni-based perovskites are promising oxygen carriers for chemical looping steam reforming to produce H 2 -rich gas from organics. In this study, a series of Fe-doped LaNiO 3 perovskites with various Ni/Fe ratios (LaNi x Fe 1-x O 3 (0 ≤ x ≤ 1)) were investigated for chemical looping steam reforming of acetic acid as a model compounds of bio-oil. Results illustrated that although LaNiO 3 showed higher activity for gas production, the Ni–Fe bimetallic perovskites were more stable during the steam reforming reactions. It was found that Fe doping can promote the content of lattice oxygen in the perovskite which could be released during the steam reforming reaction, thus coking resistant of the perovskite was effectively improved. Among the LaNi x Fe 1-x O 3 (0 ≤ x ≤ 1) perovskites, LaNi 0.8 Fe 0.2 O 3 exhibited the best synergistic effect between Ni and Fe to achieve the highest H 2 /CO for H 2 -rich gas production. Operational variables of the steam reforming reactions catalyzed by LaNi 0.8 Fe 0.2 O 3 for H 2 production were further optimized. • The doping of Fe increased the lattice oxygen of LaNiO 3 to achieve better anti-coking ability. • The Ni–Fe bimetallic perovskites were more stable than LaNiO 3 perovskite for steam reforming. • LaNi 0.8 Fe 0.2 O 3 exhibited the best synergistic effect between Ni and Fe for H 2 production. • Effect of temperature and steam/carbon ratio on LaNi 0.8 Fe 0.2 O 3 -catalyzed steam-reforming reaction was evaluated. [ABSTRACT FROM AUTHOR]

Abstract Two elements, Cu and Ni, were deliberately added into a typical medium Mn steel during smelting for further improving mechanical properties through the precipitation of Cu particles simultaneously with austenite reversed transformation (ART). The characteristics of microstructure and mechanical properties due to the addition of Cu and Ni was investigated. From the results, the feasibility that Cu-rich particles precipitate within recrystallized ferritic grains or tempered martensitic laths during ART annealing is proved, and the size of Cu-rich particles are nano-scaled, of which the diameter is less than 20 nm. The addition of Cu and Ni in medium Mn steel not only benefits the increase of reversed austenite fraction, but also the formation of a considerable amount of annealing twins during ART annealing, which contributes to split and further refine the austenite grains. Additionally, the addition of Cu and Ni enables a significant increase of tensile strength, about 90–150 MPa while do not improve the yield strength, and moreover results in the deterioration of tensile ductility. Yet even so, the optimal product of tensile strength and total elongation (PSE) is above 42 GPa%. Furthermore, it is confirmed that at high stain rates medium Mn steels still have an outstanding comprehensive properties. [ABSTRACT FROM AUTHOR]