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Artificial nitrogen fixation is emerging as a promising approach for synthesis of ammonia at mild conditions. Inspired by biological nitrogen fixation based on bacteria containing iron, zinc doped Fe 2 O 3 nanoparticles are proposed as an efficient and earth abundant electrocatalyst for converting N 2 to NH 3. In neutral media, it achieves a maximum Faradaic efficiency (FE) of 10.4% and a large NH 3 yield rate of 15.1 μg h−1 mg−1 cat. at −0.5 V vs. reversible hydrogen electrode. This catalyst also exhibits excellent selectivity and stability. Theoretical calculations suggest the reaction follows the associative enzymatic mechanism and it has a barrier of as low as 0.68 eV. • Zn–Fe 2 O 3 nanoparticles for Electrocatalytic Nitrogen Fixation to Ammonia are prepared. • Oxygen vacancy is beneficial to boost performance of nitrogen reduction reaction. • Zn–Fe 2 O 3 shows excellent stability and selectivity. • Theoretical calculations indicate an enzymatic reaction path for this catalyst. [ABSTRACT FROM AUTHOR]

In addition to the extended light absorption, the effective spatial charge separation is a crucial factor for highly efficient metal-oxide semiconductor-based photocatalysts. Herein, a rational design of metal-semiconductor-metal nano heterostructure for enhancing photocatalytic performance is proposed. The semiconductor nanoparticles are integrated with two metals in one single nano heterostructure. The disordered layers are induced on the surface of TiO 2 to promote the light absorption capacity. More importantly, the n-n+ junction is fabricated at the contact region between crystalline TiO 2 (n-TiO 2) and disordered layers (n+-TiO 2). Besides, the Schottky diode and Ohmic contact are formed on n-TiO 2 and n+-TiO 2 , respectively. As a result, the existence of multi-junctions leads to the formation of multiple continuous built-in electric fields, thus remarkably accelerating the spatial separation of charge carriers. The resulting nano heterostructure with multi-junctions (Pt–TiO 2 –H–Ag) exhibits remarkably promoted photocatalytic performance. The maximum hydrogen generation rate of Pt–TiO 2 –H–Ag under solar illumination (18001.0 μmol/h/g) is 8.3, 9.3, and 1.5 times superior to that of Pt-loaded P25 (Pt–P25), Pt loaded TiO 2 (Pt–TiO 2), and hydrogenated Pt–TiO 2 (Pt–TiO 2 –H), respectively. Moreover, the photocatalytic performance under visible illumination is significantly enhanced by Pt–TiO 2 –H–Ag. Specifically, the H 2 generation rate of Pt–TiO 2 –H–Ag (2382.7 μmol/h/g) is about 15.1, 17.2, and 1.4 times higher than that of Pt–P25, Pt–TiO 2 , and Pt–TiO 2 –H, respectively. The corresponding apparent quantum efficiency of Pt–TiO 2 –H–Ag is 15.8% (420 nm). The nano heterostructure with multi-junctions also exhibits excellent stability after five cycles, remaining hydrogen evolution rates of 15581.5 and 2211.4 μmol/h/g under solar and visible illumination, respectively. This effective and controllable manufacturing strategy could provide new opportunities to simultaneously extend optical absorption and facilitate the spatial charge separation and transport of wide-bandgap metal-oxide semiconductors. Image 1 • TiO 2 nano heterostructure with multi-junctions was fabricated. • Schottky diode, n-n+ junction, and Ohmic contact were formed on TiO 2 nanoparticles. • The multiple continuous built-in electric fields boosted the spatial charge separation. • The disordered layers induced by hydrogenation enhanced the light absorption capacity. • The apparent quantum efficiency of 15.8% (420 nm) was obtained. [ABSTRACT FROM AUTHOR]

TiO 2 mesocrystals have been considered as an efficient photocatalyst due to the effective charge transport. Introducing hydroxyls in TiO 2 is respected to reduce the energy barrier of hydrogen formation. Herein, a simple one-step fabrication of highly self-hydroxylated TiO 2 mesocrystals (MCs) for enhancing photocatalytic hydrogen evolution is proposed. TiO 2 single crystals (SCs), polycrystals (PCs) and MCs are obtained via regulating the pH of the precursor during hydrothermal treatment. Results indicate that the moderate alkaline condition is favorable for the synthesis of highly self-hydroxylated TiO 2 MCs. Compared with SCs, PCs and commercial P25 TiO 2 nanoparticles, MCs exhibit the best photocatalytic activity in H 2 evolution. Specifically, the maximum hydrogen evolution rate under solar light illumination (22.8 mmol/h/g) is 10.5 times higher than that of P25. Moreover, the MCs exhibit excellent catalytic stability and the hydrogen evolution rate can be maintained at 20.8 mmol/h/g under solar illumination after five cycles of reactions. The highly self-hydroxylated TiO 2 MCs are constructed from crystallographically oriented nanocrystals with abundant hydroxyls. The unique superstructure and large surface area of MCs enable the effective charge separation and transport. Moreover, the high density of hydroxyls can reduce the recombination rate of photo-generated free charges and energy barrier for hydrogen formation while facilitate light absorption. The synthesis of highly self-hydroxylated TiO 2 MCs and the underlying mechanism offer interesting insights for modifying the structure and properties of TiO 2 towards high-performance hydrogen evolution. Image 1 • Highly self-hydroxylated TiO 2 mesocrystals are obtained by one-step fabrication. • The moderate alkaline condition leads to mesocrystalline and abundant hydroxyls. • 10.5 times higher H 2 evolution activity under solar light is achieved. • The mesocrystals facilitate the separation and transport of carriers. • Hydroxyls reduce recombination rate of carriers and energy barrier for H 2 formation. [ABSTRACT FROM AUTHOR]

A quenching-typed electrochemiluminescence (ECL) immunosensing method was proposed for protein detection by the redox reaction of tungsten-based polyoxometalate nanoclusters (W-POM NCs) with free radical (O 2 •–) as the intermediate of co-reactant H 2 O 2. The immunosensor was constructed by co-immobilizing luminol loaded CeVO 4 /Au nanohybrids and capture antibody on an indium tin oxide electrode, which showed strong ECL emission in the presence of H 2 O 2 due to the catalysis of CeVO 4 /Au toward its electro-oxidation to produce O 2 •– via the reversible conversion between Ce3+ and Ce4+. The W-POM NCs were encapsulated in the uniformly sized amino-silica nanosphere (SiO 2) to act as a label (W-POM@SiO 2) of the secondary antibody. Upon the sandwich-typed immunoreactions with the target, the W-POM NCs were introduced onto the immunosensor surface to reduce O 2 •–, and thus quenched the ECL emission of luminol-H 2 O 2 system. Using neuron-specific enolase (NSE) as a target, the proposed method showed a detection limit of 0.19 pg/mL and detectable range of 0.5 pg/mL to 18 ng/mL. The excellent performance of the proposed "ON-OFF" strategy demonstrated that the W-based quenching offers an effective tag for immunoassay of protein biomarkers. [Display omitted] • An ECL immunosensing method is proposed using tungsten-based quencher as signal tag. • The tag can efficiently quench the ECL emission of Lu-CeVO 4 /Au/H 2 O 2 via the consumption of O 2.•−. • This immunoassay method for NSE shows good operability and high sensitivity with a LOD of 0.19 pg/mL. • The quenching effect offers an effective tag for immunoassay of protein biomarkers. [ABSTRACT FROM AUTHOR]

To explore the vertical distribution of the aerosol optical parameters over Jinhua City, southeast China, a Dual-wavelength Mie Polarization Raman Lidar (DMPRL) system was operated to obtain the atmospheric backscattering signals from June 2013 to May 2014. Profiles of aerosol occurrence frequency and aerosol optical parameters, including backscattering ratio, particle depolarization ratio, and color ratio, were retrieved from the lidar signals. The cases with a cloud base below 6 km and profiles on rainy days were eliminated. The multi-layer vertical aerosol structure was found in Jinhua area and the altitude-resolved optical properties varies with seasons. In autumn, winter and spring, the aerosol layer occurrence frequencies were higher than summer at 3–6 km, especially in spring. The mean particle depolarization ratio at 4–6 km exceeded 0.1 in autumn, winter, and spring, whereas it was <0.05 in summer. Aerosol with high color ratios appeared at 0–2 km in autumn. The analysis of one-year backward trajectories exhibits a dust dominating aerosol layer at 4–6 km in autumn, winter, and spring, a partially sea salt dominating aerosol layer at 0–2 km in autumn and a partially dust aerosol layer at 0–2 km in winter. Six cases were used to study the influence of aerosol advection and local sources vertical aerosol properties distribution. Through our analysis, aerosols at different altitudes are influenced by different sources, which are important for understanding the spatiotemporal characteristics of aerosol layers over Jinhua. The vertical distribution of aerosol properties in Jinhua area is affected by locally emitted aerosol , transported dust and ocean aerosol. • Multi-layer aerosol with corresponding properties observed by lidar over Jinhua. • High occurrences of aerosol layers were found at 3–6 km except summer. • Source-related aerosol vertical distribution dominated especially at 4–6 km. • Larger particles with high color ratios appeared at 0–2 km in autumn. • Regional and transported source aerosols affected the vertical aerosol properties. [ABSTRACT FROM AUTHOR]

A benign thermal stress in solid oxide fuel cell is of great importance for its stability and the interfaces between different components suffer from unexpected risks of instability such as electrode delamination and crack due to varying thermal expansion coefficients. Besides, chromium poisoning cathode materials leads to phase changes, which possibly induces thermal stresses at the interface of electrolyte and cathode. A three dimensional model at the microscale level is thus developed to unravel the effect of thermal stress on the interface. The model is constructed by governing equations including heat, species, momentum, ion and electronic transportation. The contact modes between the active cathode and electrolyte are studied to reveal the cell performance and thermal stresses, which are strongly related to the number of contact sites and the contact area. Moreover, chromium poisoning the contact causes the disordered distribution of thermal stresses with the increase of the contact sites, worsening the cell current density and durability. The resulting conclusions are expected to offer a solution to avoid possible fatal mechanical failure due to unfavorable interface design and chromium attack. [ABSTRACT FROM AUTHOR]

• A flexible dynamic model and a universal networking method of gas networks. • Fully and quantitatively discussions on model accuracy and its influence factors. • Simple application evaluation by a practical energy internet case. • The model is easy to implement and can greatly enhance simulation speed. • The model is particularly fit for studies of gas-electricity coupling. The couplings between different types of energy networks are receiving increasing attention, especially in distribution networks. One of the fundamental topics of interest is the dynamic coupling between power grids and gas networks. To study dynamics in gas pipelines and the interaction between gas networks and electric power grids, dynamic modeling of gas networks gives the foundation. Commercial software is available and mature, but has flaws: (1) time-consuming simulation and complex implementation, and (2) the interface to electric power grids is not friendly. In this paper, transfer functions (TFs) are used to model a single pipeline. To model a gas network with multiple pipelines, a universal networking method is proposed. The accuracy of transfer function models are thoroughly examined under step and sinusoidal excitations, and the influence factors of accuracy is investigated. The adaptability of TF models is then quantitated by reference curves. Finally, the proposed modeling approach is applied in analyzing a gas-electricity system to test its capabilities. [ABSTRACT FROM AUTHOR]

Environmental cadmium (Cd) exposure is a serious public health concern, as the kidney is the primary target for Cd exposure. The present study aimed to investigate the role and underlying mechanisms of nuclear factor erythroid-derived 2-like 2 (Nrf2) in renal fibrosis induced by chronic Cd exposure. Nrf2 knockout (Nrf2 -KO) mice and their wild-type littermates (Nrf2 -WT) were exposed to 100 or 200 ppm Cd in drinking water for up to 16 or 24 weeks. Following the Cd exposures, Nrf2 -KO mice showed elevated urinary neutrophil gelatinase-associated lipocalin (NGAL) and BUN levels compared to Nrf2 -WT mice. Masson's trichrome staining and expression of fibrosis-associated proteins revealed that more severe renal fibrosis occurred in Nrf2 -KO than that in Nrf2 -WT mice. Renal Cd content in the Nrf2 -KO mice exposed to 200 ppm Cd was lower than that in Nrf2 -WT mice, which might be a consequence of the severe renal fibrosis in the Nrf2 -KO mice. Mechanistic studies showed that Nrf2 -KO mice exhibited higher levels of oxidative damage, lower antioxidant levels, and more regulated cell death, apoptosis in particular, than those in Nrf2 -WT mice caused by Cd exposure. In conclusion, Nrf2 -KO mice were more prone to develop renal fibrosis induced by chronic Cd exposure, partially due to a weakened antioxidant, detoxification capacity and increased oxidative damage. [Display omitted] [ABSTRACT FROM AUTHOR]

Soil fungi play key roles in agricultural ecosystem. Yet, little is currently known about the dynamic pattern and driving factors of the rare and abundant fungal subcommunities in response to the short- and long-term continuous cropping. Here, we comparatively investigated the diversity and structure of rare and abundant fungal subcommunities with varying histories of continuous chrysanthemum (Chrysanthemum morifolium Ramat.) cropping, that is, cropping for 1 year (CP1), 6 years (CP6) and 12 years (CP12). The alpha diversity (estimated as Shannon index) of abundant and especially rare fungal subcommunities increased with continuous cropping years. The structure of both rare and abundant subcommunities varied notably with the increasing of continuous cropping years, but the value of dissimilarity for rare taxa (average of 0.988) was significantly higher than for abundant taxa (average of 0.243). The abundant taxon Mortierellomycota and rare taxa Nitrospirae and Elusimicrobia were significantly enriched in the CP12 treatment. Soil rare fungal taxa were mainly affected by the available nutrients (i.e., carbon, nitrogen and phosphorus) and pH, while the abundant fungal taxa were majorly influenced by soil total nutrients. The growth indicators (e.g., plant biomass, plant height, and flower diameter) of cut chrysanthemum significantly decreased under 12-year continuous cropping system. Random forest models showed that abundant rather than rare fungi played key roles in the chrysanthemum growth even though the rare fungi were more significantly affected during continuous cropping. [ABSTRACT FROM AUTHOR]

Stormwater runoff has become a major anthropogenic urban pollution source that threatens water quality. In this study, coagulation-sedimentation, and ammonium ion exchange and regeneration (AIR) modules were coupled as a CAIR system to efficiently treat stormwater runoff. In the coagulation module, 99.3%, 91.7%, and 97.0% of turbidity, total phosphorus, and chemical oxygen demand could be removed at an optimized poly-aluminum ferric chloride dosage of 30 mg/L, and the continuous experiment confirmed that the full load mode was more suitable for its rapid start-up. In the AIR module, dynamic ammonium removal indicated that the breakthrough time decreased with the rising initial concentration and superficial velocity. The Modified Dose Response (MDR) model described the ammonium exchange behavior better than the Thomas and the Bohart-Adams models. Then, a design flow of the ion exchange reactor was constructed by correlating constants in the MDR model with engineering parameters, and the ion exchange reactor was designed for continuous operation of the CAIR system. The average concentrations of chemical oxygen demand, total phosphorus, ammonium nitrogen, and total nitrogen in the effluent of the CAIR system were 7.22 ± 2.26, 0.17 ± 0.05, 1.49 ± 0.01, and 1.62 ± 0.02 mg/L, respectively. The almost unchanged exchange capacity and physicochemical properties after the multicycle operation confirmed the durability of zeolite for ion exchange. Techno-economic analysis suggested that the CAIR system is practically promising for stormwater management with efficient pollutants removal, small footprint, and acceptable operating cost. [Display omitted] • A CAIR system was constructed by coagulation and NH 4 + exchange-regeneration (AIR). • The CAIR efficiently removed particles, COD and nutrients from stormwater runoff. • A design flow for AIR was proposed based on a dynamic model of packed column. • The durability of zeolite for ion exchange was confirmed by multicycle operation. • CAIR proposed by the design flow is inspirable for space-saving stormwater management. [ABSTRACT FROM AUTHOR]

A novel controlled release system-based homogeneous immunoassay protocol (CRSHIP) was developed for the detection of squamous cell carcinoma antigen (SCCA). The positively charged aminated polystyrene microsphere (APSM) used as molecular gate was capped on the pores of the negatively charged antibody-conjugated magnetic mesoporous Fe 3 O 4 (Ab-Fe 3 O 4 ) by electrostatic interaction to achieve encapsulation of toluidine blue (TB). With the addition of SCCA, APSM was replaced from Ab-Fe 3 O 4 due to the specific binding of antibody to antigen, and then the trapped TB was released from the pores. The released TB could be detected by square wave voltammetry and the signal could be correlated with the amount of SCCA. The developed CRSHIP displayed a high current response, a relatively wide linear range (from 0.001 to 4.0 ng/mL) and a low detection limit (0.33 pg/mL) for the detection of SCCA. The method showed high selectivity and good reproducibility. In addition, the CRSHIP provided a simple, fast and sensitive approach for the detection of SCCA in serum sample. [ABSTRACT FROM AUTHOR]

[Display omitted] • A CAIRM process was developed by coagulation, NH 4 + exchange – regeneration, and MBR. • CAIRM obtained effluent with 0.3 mg/L NH 4 + and 2.3 mg/L TN within total HRT of 4.6 h. • Long-term operation didn't impair NH 4 + exchange capacity of exchangers. • Membrane fouling was alleviated in MBR with large sludge flocs and good bioactivity. • CAIRM will address insufficient N removal and large footprint of conventional WWTPs. Chemically enhanced primary treatment (CEPT), ammonium ion exchange and regeneration (AIR) and membrane bioreactor (MBR) were coupled as CAIRM to treat domestic wastewater compactly and efficiently. CAIRM achieved efficient removal of chemical oxygen demand, ammonia nitrogen, total nitrogen (TN) and total phosphorus with total hydraulic retention time of 4.6 h, and obtained 2.3 ± 0.9 mg/L TN in the effluent. CEPT removed phosphate and impurities and prevented AIR from pollution. AIR maintained excellent nitrogen removal with a slight decrease in the exchange capacity of ion exchangers. MBR polished the effluent from AIR, and the larger particle size and better dewaterability of sludge mitigated the membrane fouling. Many heterotrophic genera, such as Rhodobacter and Defluviimonas , were enriched in the oligotrophic MBR. This study demonstrates the viability and stability of CAIRM in efficient wastewater treatment, which will address critical challenges in insufficient nitrogen removal and high land occupancy of current processes. [ABSTRACT FROM AUTHOR]

Disorder modification of TiO 2 nanocrystals (NCs) has been proved to enhance the photocatalytic activity through surface defects and band-gap narrowing. In this contribution, we used a facile way of ultrasonic irradiation to induce the hydroxyls injection into TiO 2 (P25) crystal lattice, which obtained disordered TiO 2 NCs. In order to improve the degree of ultrasonic-induced disorder, extension of ultrasonic time or increasing alkalinity was necessary, which continuously regulated the energy band structure of TiO 2 and could at most improve the solar-driven photocatalytic activity for 2.33 times than original P25 NCs. [ABSTRACT FROM AUTHOR]

In order to carry out the physical simulation of interfacial microstructure evolution for hot compression bonding behavior in linear friction welded joints of GH4169 superalloy, the novel hot isothermal compression bonding tests were performed on a Gleeble-3500 thermal simulator in the temperature range of 970 °C to 1150 °C and at the strain rate range of 0.01 s − 1 to 10 s − 1 . The macroscopic morphology of hot compression GH4169 bonded joints at different parameters were observed by the optical microscope (OM). The interfacial microstructure evolution in the hot compression bonded joints of GH4169 superalloy were investigated by the OM and the scanning electron microscope (SEM). FEM simulation of the hot compression bonding process was given in this paper. The defects in the joints interface were observed by SEM, and the interfacial oxidation of the compression bonded joints was discussed. [ABSTRACT FROM AUTHOR]

Through thermal decomposition of hybrid carbonate (Cu, Co) 2 (OH) 2 CO 3 precursors synthesized by a simple carbonate-assisted hydrothermal method, porous hierarchical Co 3 O 4 /CuO composites with different ratios of Co to Cu were successfully fabricated. A cooperative self-assembly effect of different carbonates has been proposed to explain the formation of nanosheets assembled hierarchical (Cu, Co) 2 (OH) 2 CO 3 precursor. Electrochemical lithium storage properties of all the composites are evaluated as anode materials for lithium-ion batteries. It is found that the ratio of Co to Cu plays a vital role in affecting the morphology, structure and subsequent electrochemical performance of the Co 3 O 4 /CuO composites. Owing to the superior porous hierarchical structure and synergistic lithium storage effect of both active electrode materials, the Co 3 O 4 /CuO composites demonstrate higher capacities and enhanced cycling stability compared to pure Co 3 O 4 or CuO electrodes. The Co 3 O 4 /CuO composite (Co: Cu = 6: 1) electrode delivers a high reversible capacity of 1056 mAh g −1 at a current density of 200 mA g −1 for 500 cycles. With the superior electrochemical performance and easy preparation, the porous hierarchical Co 3 O 4 /CuO composites demonstrate promising application potential as anode materials for next generation high performance LIBs. [ABSTRACT FROM AUTHOR]

TiO 2 mesoporous single crystals (MSCs) with diverse constructions in a controllable fashion are successfully fabricated by a new template-free method for the first time, using oxalic acid (OA) as the pore-forming agent and morphological controller. Unlike the seeding-template based growth mechanism, the TiO 2 MSCs in the present work may involve a process of oriented aggregation and crystallographic fusion of primary nanocrystals. The structural control of TiO 2 MSCs can be easily realized by tailoring growth conditions, such as Ti-source concentration and OA dosages. Moreover, the TiO 2 MSCs shows substantial improvement in lithium specific capacity from 0.2 C to 10 C in comparison to the reference TiO 2 nanoparticle. The high-rate performance was further improved by fabricating MSCs/graphene oxide nanocomposites, and specific capacity of the composite at the rate of 20C is as high as 90 mA h g −1 . This new template-free strategy may open up new and exciting opportunities for the preparation of other MSCs, and makes important applicatory significance for the structure design of high-rate lithium ion battery anodes. [ABSTRACT FROM AUTHOR]

[Display omitted] • The first comprehensive description of the relationship between air pollution and hospital admissions, length of stay, and costs for patients with cardiovascular disease with comorbid diabetes mellites. • First application of WHO 2021 air quality standards to a real-world study. • PM 2.5 and PM 10 are positively associated with hospital admissions, hospital cost and length of hospital stay for patients with cardiovascular disease with comorbid diabetes mellites. • Policy changes to reduce air pollutants exposure may reduce cardiovascular disease with comorbid diabetes mellites admissions and substantial savings in health care spending and hospital stay. Evidence on the effects of the air pollutants on the hospital admissions, hospital cost and length of stay (LOS) among patients with comorbidities remains limited in China, particularly for patients with cardiovascular diseases and comorbid diabetes mellitus (CVD-DM). We collected daily data on CVD-DM patients from 242 hospitals in Beijing between 2014 and 2019. Generalized additive model was employed to quantify the associations between admissions, LOS, and hospital cost for CVD-DM patients and air pollutants. We further evaluated the attributable risk posed by air pollutants to CVD-DM patients, using both Chinese and WHO air quality guidelines as reference. Per 10 ug/m3 increase of particles with an aerodynamic diameter < 2.5 μm (PM 2.5), particles with an aerodynamic diameter < 10 μm (PM 10), sulfur dioxide (SO 2), nitrogen dioxide (NO 2), carbonic oxide (CO) and ozone (O 3) corresponded to a 0.64% (95% CI : 0.57 to 0.71), 0.52% (95% CI : 0.46 to 0.57), 0.93% (95% CI : 0.67 to 1.20), 0.98% (95% CI : 0.81 to 1.16), 1.66% (95% CI : 1.18 to 2.14) and 0.53% (95% CI : 0.45 to 0.61) increment for CVD-DM patients' admissions. Among the six pollutants, particulate pollutants (PM 2.5 and PM 10) in most lag days exhibited adverse effects on LOS and hospital cost. For every 10 ug/m3 increase in PM 2.5 and PM 10 , the absolute increase with LOS will increase 62.08 days (95% CI : 28.93 to 95.23) and 51.77 days (95% CI :22.88 to 80.66), respectively. The absolute increase with hospital cost will increase 105.04 Chinese Yuan (CNY) (95% CI : 49.27 to 160.81) and 81.76 CNY (95% CI : 42.01 to 121.51) in PM 2.5 and PM 10 , respectively. Given WHO 2021 air quality guideline as the reference, PM 2.5 had the maximum attributable fraction of 3.34% (95% CI : 2.94% to 3.75%), corresponding to an avoidable of 65,845 (95% CI : 57,953 to 73,812) patients with CVD-DM. PM 2.5 and PM 10 are positively associated with hospital admissions, hospital cost and LOS for patients with CVD-DM. Policy changes to reduce air pollutants exposure may reduce CVD-DM admissions and substantial savings in health care spending and LOS. [ABSTRACT FROM AUTHOR]

High temperature chloride corrosion tests of AlFe 2.5 NiMoNbCr high-entropy alloy were carried out comparing with those of Inconel625 and AlFeNiMoNb plate. Uniform dispersion of elements in the Cr depletion zone existed during the corrosion process of AlFe 2.5 NiMoNbCr high-entropy alloy promoted the formation of continuous Al 2 O 3 layer, and the dendritic Al 2 O 3 improved the adhesion of the corrosion layer through "oxide pegging" mechanism. Observation of metal chloride oxides on the samples sealed for several days at R.T. supplemented the reaction of high temperature chlorine corrosion. Al 2 O 3 /Cr 2 O 3 double-layer makes AlFe 2.5 NiMoNbCr have better potential application value than Inconel625 with a single Cr 2 O 3 layer. • AlFe 2.5 NiMoNbCr HEA was obtained. • Observation of metal chloride oxides. • Al 2 O 3 /Cr 2 O 3 double-layer formed on AlFe 2.5 NiMoNbCr surface. • Dendritic Al 2 O 3 in the HEA improved the adhesion of the corrosion layer. [ABSTRACT FROM AUTHOR]

• Effect of salinity level and gradient on partial nitrification was studied by PN-MBR. • PN-MBRs obtained stable nitrite accumulation and ammonium removal at 10 g/L NaCl. • Salinity stimulated EPS secretion with higher carbohydrates contents. • Salinity differentiated AOBs and NOBs, and enriched AOBs for partial nitrification. • Salt gradients induced different nitrification pathways for at the same salinity. Effects of salinity level and gradient on partial nitrification performance, sludge properties and microbial activities were investigated using partial nitrification membrane bioreactors (PN-MBRs). PN-MBRs obtained stable nitrite accumulation rate of 91.1% and ammonia removal of 64.8% at 10 g/L NaCl. 10 g/L NaCl obtained higher oxygen uptake rate than 5 g/L, and promoted the differentiation of ammonium-oxidizing bacteria (AOB) and nitrite-oxidizing bacteria. Salinity increased sludge flocs size, stimulated secretion of extracellular polymeric substances with high carbohydrates contents, but had insignificant impact on sludge settleability and dewaterability. Salt level and gradient were both important for microbial community evolution to salt-tolerant bacteria. PN-MBRs enriched aerobic AOBs (Nitrosomonas and norank_f_Nitrosomonadaceae) and anaerobic AOBs (Candidatus_Kuenenia and Candidatus_Brocadia) for partial nitrification, while salt gradients resulted in different metabolism pathways for nitrification even at the same salinity. Increasing salinity promoted hydroxylamine oxidizer in nitrification process evolving from Candidatus_Kuenenia and Candidatus_Brocadia to aerobic AOBs. [ABSTRACT FROM AUTHOR]

• An NH 4 +-N adsorption and regeneration (AIR) unit was constructed to remove nitrogen. • A novel process of chemical coagulation, AIR and biological aerated filter was built. • The process achieved COD < 20, NH 4 +-N < 1.0, TN < 3.0 and TP < 0.3 mg/L at HRT 4.6 h. • The biological aerated filter enriched faster-growing heterotrophic bacteria. • The process saved 60% land occupation and obtained treatment cost of $ 0.155/m3. In this study, an ammonia nitrogen (NH 4 +-N) ion exchange (IE) and regeneration (AIR) was constructed, and the chemical enhanced primary treatment (CEPT), AIR and biological aerated filter (BAF) were coupled in series to construct a novel CEPT-AIR-BAF process for efficient pollutants removal. At total hydraulic retention time of 4.6 h, the pilot-scale CEPT-AIR-BAF system obtained effluent with chemical oxygen demand of 17.9 ± 6.0 mg/L, NH 4 +-N of 0.5 ± 0.3 mg/L, total nitrogen of 2.4 ± 1.0 mg/L and total phosphorus of 0.08 ± 0.05 mg/L. AIR module achieved outstanding NH 4 +-N IE performance with NaClO-NaCl regeneration, and long-term regeneration increased surface area and mesopore of zeolites. Faster-growing heterotrophic bacteria, such as Pseudomonas and Comamonas , were enriched in BAF. The CEPT-AIR-BAF system saved at least 60% of land occupation and upfront investment, and the treatment cost ($ 0.155/m3) should be further reduced by investigations on the regeneration of loaded zeolite. [ABSTRACT FROM AUTHOR]

• Dynamic aggregation of stratified load clusters for transient voltage stability. • Unstable load clusters are filtrated by a fast estimation of critical clearing time. • Load grouping by analysis on the state variable expanded model. • Load aggregation based on the weighted average of internal potential angles. • Fast aggregation is hopefully applied to online scenarios. Transient voltage instability always starts from low-voltage load areas and burgeons to high-voltage grids, where the dynamic load is one significant factor. There is an urgent demand for effective and efficient modeling of electrical loads. Thereby, this paper proposes a classification and aggregation approach to model the multi-voltage-level load clusters. Load clusters from online identification are classified and grouped according to their stabilities and transient characteristics. Then, based on the weighted average of induction motor (IM) voltage angles, an approach is proposed to aggregate models of grouped loads sharing similar dynamic features. The proposed approach can aggregate load models from a low voltage level to a higher one layer by layer. Thus, the aggregated model keeps the primary transient characteristics, as well as dramatically reduces the simulation scale and the calculation complexity. [ABSTRACT FROM AUTHOR]

• Biological nutrient removal in anaerobic side-stream reactor (ASSR) was studied. • Inserting ASSR and packing carriers enhanced nitrogen removal and sludge reduction. • ASSR and carriers both favored denitrifiers enrichment and organic matters release. • ASSR deteriorated biological phosphorus removal owing to low sludge discharge. • Denitrification and sludge decay in ASSR played important roles in nutrient removal. An anoxic-aerobic membrane bioreactor (AO-MBR), an anaerobic side-stream reactor (ASSR) coupled MBR (A-MBR), and an MBR with ASSR packed with carriers (AP-MBR) were operated parallelly to investigate biological nutrient removal, microbial community structure and mass balance of nutrients in sludge reduction systems. Compared to AO-MBR, A-MBR and AP-MBR were both efficient in COD and NH 4 +-N removal, had significantly higher nitrogen removal, reduced sludge production by 35.0% and 45.9%, but deteriorated biological phosphorus removal. Nitrosomonadaceae and Nitrospira were major bacteria responsible for ammonium and nitrite oxidation in the three systems. Inserting ASSR and packing carriers both favored denitrifying bacteria enrichment and organic substances release, and thus resulted in higher nitrate uptake rate (NUR) in the anoxic tank. Higher endogenous NUR in ASSR than in anoxic tank also indicated that ASSR and carriers both accelerated sludge decay. Denitrification and sludge reduction occurred in ASSR played important roles in biological nutrient removal. [ABSTRACT FROM AUTHOR]