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Synthesis of organic compounds often necessitates rigorous reaction conditions or the involvement of hazardous oxidants, resulting in substantial energy consumption and considerable environmental damage. Photocatalytic selective oxidation represents a green and environmentally friendly way to obtain high‐value chemicals, which has developed rapidly in recent years. Bismuth‐based (Bi‐based) semiconductor materials have gained intense interest in selective organic synthesis due to their diverse crystal structures and compositions, tunable band structure, and outstanding photocatalytic performance. Herein, a systematic summary of the solar‐driven selective oxidation over varieties of Bi‐based semiconductors is provided. Initially, the reactive species involved in selective oxidation, Bi‐based materials widely used in photocatalytic selective oxidation, and the methods for synthesizing these Bi‐based materials are meticulously classified. Concerning their selective oxidation reactions, a variety of modification strategies, with a focus on the separation of photogenerated carriers and the regulation of reactive species is extensively documented. Highlights are the diverse applications and mechanism discussions of Bi‐based photocatalysts in the oxidation reactions, including alcohol oxidation, C─H bond activation, amine oxidation, and sulfide oxidation, as well as the coupling reactions with photoreduction. Finally, the future development prospects and challenges of Bi‐based photocatalysts in the field of selective oxidation is proposed, hoping to provide valuable insights and guidance for the design of photocatalysts for selective oxidation. [ABSTRACT FROM AUTHOR]

The development of a long-term and sustainable energy economy is one of the most significant technological challenges facing humanity. Photoelectrochemical (PEC) technology is considered as the most attractive route for converting solar energy into chemical energy. However, the slow reaction kinetics of PEC oxidation and reduction greatly hinder its practical application. To address this issue, engineering photoelectrodes with various defects can significantly improve their catalytic performance, which can not only regulate catalyst electronic structure but also promote charge transfer/separation by serving as an active/adsorption/energy storage site. Herein, the defect engineering strategies for photoelectrodes are systematically summarized, focusing on the latest progress in defective photocathode for energy conversion. First, an overview of defect types, basic principles of photocathode, and the positive role of defects in the photocathode are provided. Second, the construction strategies and characterization methods of defective photocathode are summarized. Then, the progress of typical energy conversion applications, including hydrogen production, CO2 reduction, and nitrogen reduction over defective photocathode, is reviewed, highlighting the crucial role of defects in high catalytic performance. Finally, the challenges and future prospects of defective photocathode are discussed, aiming to bring new opportunities for the development of photocathode through defect engineering. [ABSTRACT FROM AUTHOR]

Climate change can induce phytoplankton blooms (PBs) in eutrophic lakes worldwide, and these blooms severely threaten lake ecosystems and human health. However, it is unclear how urbanization and its interaction with climate impact PBs, which has implications for the management of lakes. Here, we used multi‐source remote sensing data and integrated the Virtual‐Baseline Floating macroAlgae Height (VB‐FAH) index and OTSU threshold automatic segmentation algorithm to extract the area of PBs in Lake Dianchi, China, which has been subjected to frequent PBs and rapid urbanization in its vicinity. We further explored long‐term (2000–2021) trends in the phenological and severity metrics of PBs and quantified the contributions from urbanization, climate change, and also nutrient levels to these trends. When comparing data from 2011–2021 to 2000–2010, we found significantly advanced initiation of PBs (28.6 days) and noticeably longer duration (51.9 days) but an insignificant trend in time of disappearance. The enhancement of algal nutrient use efficiency, likely induced by increased water temperature and reduced nutrient concentrations, presumably contributed to an earlier initiation and longer duration of PBs, while there was a negative correlation between spring wind speed and the initiation of PBs. Fortunately, we found that both the area of the PBs and the frequency of severe blooms (covering more than 19.8 km2) demonstrated downward trends, which could be attributed to increased wind speed and/or reduced nutrient levels. Moreover, the enhanced land surface temperature caused by urbanization altered the thermodynamic characteristics between the land and the lake, which, in turn, possibly caused an increase in local wind speed and water temperature, suggesting that urbanization can differently regulate the phenology and severity of PBs. Our findings have significant implications for the understanding of the impacts of urbanization on PB dynamics and for improving lake management practices to promote sustainable urban development under global change. [ABSTRACT FROM AUTHOR]

Differential evolution (DE) is known among the best methods for solving real-world optimization problems owing to its simple and efficient nature. Since almost all real-world applications are constrained optimization problems, constraint handling techniques are required for differential evolution algorithms. Conventional constraint handling techniques for DE mainly focus on discarding or devaluing the infeasible solutions, leading to an information loss of the infeasible region. To strike the balance between the explorations of the feasible region and the infeasible region, we look into the bi-objective space constituted by the objective function and the total constraint violation, and define the infeasible solution which has the lowest degree of constraint violation and lies in the Pareto front as the best infeasible solution. We discuss how the best infeasible solution help improve the current best solution. Based on this, we propose an improved differential evolution algorithm with adaptive ranking-based constraint handling technique (AR-DE). First, we start by identifying the best feasible solution and the best infeasible solution of the current population. Second, to guide the population evolving toward these solutions, different mutation and selection operators are proposed. Third, we design the adaptive control to automatically choose the operators to fit different stages of the evolution and various situations of the population. We conduct experimental studies by comparing with other widely used constraint handling techniques based on the cardinal version of differential evolution for fair competition. Standard test problems and five well-known engineering constrained optimization design problems are used to evaluate the effectiveness of AR-DE. Statistical outcomes show that the overall results of AR-DE are better than those of the other comparing methods. We also investigate the ability of AR-DE to obtain feasible solutions, and tune the parameters to achieve better performance. [ABSTRACT FROM AUTHOR]

Alite-belite-ye'elimite (ABY) cement is considered to be eco-cements with adequate mechanical properties and fewer CO 2 emissions. The phase assemblage and ye'elimite content of ABY cement play a very important role in cement properties. In this study, ABY clinkers with increasing ye'elimite percentage (0.3 wt%-36.4 wt%) were prepared at 1300 °C and the phase composition was characterized by Rietveld Quantitative Phase Analysis combined with energy dispersive X-ray spectrometry. The ye'elimite formed with a calculated composition of Ca 3.92 Mg 0.02 Al 2.81 Fe 0.05 Si 0.04 S 1.16 , incorporating additional sulfur compared to the theoretical value. In addition, the hydration properties of heat evolution, hydration products and compressive strength of ABY cement are studied. The result shows that the increase of ye'elimite content leads to a more intense initial heat release and a higher cumulative heat release. The presence of ye'elimite inhibits the hydration of alite at early ages. ABY mortars with increasing ye'elimite (15.8 wt%) exhibited a higher strength (29.6 MPa) at 3 days by the contribution of ye'elimite hydration, and an increase (47.4 MPa) at 28 days. An adequate proportion of ye'elimite (<15 wt%) is favorable to the performance of ABY cement, and releases 12 % less CO 2. • ABY clinkers with a high coexistence of alite and ye'elimite were prepared. • Ye'elimite has a higher S atom and alite riches in the Zn atom in ABY clinker. • The presence of ye'elimite retards alite hydration adverse to later strength. • Adequate ye'elimite < 15 wt% favors strength development. [ABSTRACT FROM AUTHOR]

The light and stress dual-responsive Bi 2 O 2 (OH)NO 3 /BiOI heterojunction is developed, and the synergy of interfacial electric field and piezoelectric polarization enables it exceptional piezo-photocatalytic performance. [Display omitted] • Bi 2 O 2 (OH)NO 3 /BiOI type-II heterostructure is created through in-situ deposition. • Bi 2 O 2 (OH)NO 3 /BiOI has 1.6 times higher surface potential than BON, suggesting a stronger electric field. • Built-in electric field and piezoelectric polarization greatly enhances charge separation. • It shows exceptional piezo-photocatalytic TH degradation of 80 % within just 10 min. Effective removal of recalcitrant pollutants is crucial for environmental protection. Tetracycline hydrochloride, as a representative recalcitrant organic pollutant, poses a potential threat to environmental integrity when present in aquatic ecosystems. Coupling piezoelectric polarization, capable of considerably promoting the photocharge separation, acts as a very prevalent and attractive strategy to improve the photocatalytic activity. In this study, an efficient piezo-photocatalytic system was developed in Bi 2 O 2 (OH)NO 3 /BiOI heterojunction by collaborating with interfacial electric field and vibration-induced piezoelectric polarization. The construction of type II heterojunction allows an interfacial electric field to propel the photogenerated electrons from BiOI to Bi 2 O 2 (OH)(NO 3) under visible light irradiation. The introduction of vibration-induced piezoelectric polarization field strengthens the interfacial electric field, which further promote the separation and migration of photogenerated charges. Profiting from the above advantages, Bi 2 O 2 (OH)(NO 3)/BiOI heterojunction exhibited a remarkable piezo-photocatalytic performance, achieving an over 80% degradation efficiency of tetracycline hydrochloride within 10 min, which far surpasses that under individual photocatalysis or ultrasound-induced piezocatalysis and also exceeds most of the previously reported piezo-photocatalysts. The combination of electron paramagnetic resonance, piezoresponse force microscopy, COMSOL simulation, and photoelectrochemical tests are conducted to probe the synergistically-catalytic mechanism. This work not only elucidates the comprehensive impact of interfacial electric field and piezoelectric polarization on charge separation, but also highlights the tremendous potential of piezo-photocatalysis for environmental remediation. [ABSTRACT FROM AUTHOR]

[Display omitted] • 2-Fluoro-4-iodoaniline was used to passivate perovskite films surface defects. • N of NH 2 group affords lone pair electron to Pb2+ to form coordinate bond. • Efficiency of passivated planar perovskite solar cells was improved to 23.44%. • Defect passivation also enhanced stability of the perovskite solar cell. An organic molecule, 2-Fluoro-4-iodoaniline (FID), is adopted to passivate the surface defects of (FAPbI 3) 0.95 (MAPbBr 3) 0.05 perovskite films. The amino group of FID forms a coordinate bond with the uncoordinated lead ion on the perovskite surface via Lewis acid–base interaction, which significantly reduced the defect state density, suppressed carrier nonradiative recombination, and boosted carrier transport of the perovskite films, resulting in increased open circuit voltage (V oc) and fill factor (FF) of the perovskite solar cells (PSCs). Meanwhile, fluorine group of FID forms hydrogen bond with perovskite, restraining ions moving and decomposition of perovskite. Consequently, the power conversion efficiency (PCE) of the PSCs was increased from 21.07% to 23.44%. Moreover, FID passivation also improved the ambient stability of the PSCs. The unencapsulated PSC with FID passivation retained more than 90% of its initial PCE for over 1500 h of storage under ambient conditions. [ABSTRACT FROM AUTHOR]

This review provides a comprehensive overview of recent progress on the three major functions of metals in the CO 2 photoreduction system, namely co-catalysts, single atom catalysts, and electronic media in all-solid-state Z-scheme junction. [Display omitted] • The main fundamentals and principles of CO 2 reduction are introduced. • The role of as co-catalyst in the CO 2 photoreduction is summarized. • The role of metal in the form of single atom catalyst is summarized. • Function of metal as electronic media in all-solid-state Z-scheme junction is presented. • Challenges and outlooks for developing efficient CO 2 reduction catalysts are proposed. Using abundant solar energy resources to mitigate the negative impact of CO 2 provides an effective way for the green development of human society. Photocatalytic and photoelectrochemical CO 2 reduction still face certain difficulties because of the unfavorable thermodynamics and slow kinetics of CO 2 reduction. In recent years, the combination of metal and photocatalyst is a promising strategy to improve the performance of photocatalyst and photocathode and made exciting progress in the field of CO 2 photoreduction. Here, we summarize recent advances on the role of metals in photocatalysis and photoelectrochemical CO 2 reduction. The main fundamentals and principles of CO 2 reduction are first introduced, and the three major functions of metal in the CO 2 photoreduction system, that are co-catalysts, single atom catalysts, and electronic media in all-solid-state Z-scheme junction, are then thoroughly summarized. In general, metal is most commonly used as co-catalyst and the loading is straightforward, and single atom performs more prominently in enhancing reactivity, while the role of electronic media in Z-system junction offers a more optimal method for building multiple composite catalysts. Finally, challenges and outlooks for developing mechanism-guided photocatalysts and photocathodes with high performance are proposed. This review is expected to facilitate the understanding on diverse functions of metal and rational design of efficient photocatalytic and photoelectrochemical systems. [ABSTRACT FROM AUTHOR]

[Display omitted] • Sn doped Cu 2 O (Cu 2 O:Sn) was firstly prepared by mixing and annealing. • A new and strong PL at 842 nm was observed in Cu 2 O:Sn at room temperature. • Cu 2 O:Sn should have good photoelectric properties and device performance. Photoluminescence (PL) is a direct embodiment of photoelectric characteristics of a material. In this work, tin (Sn) doped cuprous oxide (Cu 2 O) Cu 2 O:Sn was prepared through mixing copper oxide (CuO) and tin sulfide (SnS) and annealing in nitrogen. By optimizing the mole ratios of CuO to SnS and annealing temperature, a new and strong near infrared PL (842 nm) was observed at room temperature in the prepared polycrystalline Cu 2 O:Sn. The 842 nm luminescence can be ascribed to the transition of carriers from Sn impurity level to the valence band edge of Cu 2 O. The results indicate that Cu 2 O:Sn has good photoelectric properties and Sn doping of Cu 2 O is a promising approach to improve the performance of Cu 2 O photoelectric devices. [ABSTRACT FROM AUTHOR]

Phytoplankton blooms have caused many serious public safety incidents and eco-environmental problems worldwide and became a focus issue for research. Accurate and rapid monitoring of phytoplankton blooms is critical for forecasting, treating, and management. With the advantages of large spatial coverage and high temporal resolution, remote sensing has been widely used to monitor phytoplankton blooms. Numerous advances have been made in the remote sensing of phytoplankton blooms, biomass, and phenology over the past several decades. To fully understand the development history, research hotspots, and future trends of remote-sensing technology in the study of phytoplankton blooms, we conducted a comprehensive review to systematically analyze the research trends in the remote sensing of phytoplankton blooms through bibliometrics. Our findings showed that research on the use of remote-sensing technology in this field increased substantially in the past 30 years. "Oceanography," "Environmental Sciences," and "Remote Sensing" are the most popular subject categories. Remote Sensing of Environment, Journal of Geophysical Research: Oceans, and International Journal of Remote Sensing were the journals with the most published articles. The results of the analysis of international influence and cooperation showed that the United States had the greatest influence in this field and that the cooperation between China and the United States was the closest. The Chinese Academy of Sciences published the largest number of papers, reaching 542 articles. Keyword and topic analysis results showed that "phytoplankton," "chlorophyll," and "ocean" were the most frequently occurring keywords, while "eutrophication management and monitoring," "climate change," "lakes," and "remote-sensing algorithms" were the most popular research topics in recent years. Researchers are now paying increasing attention to the phenological response of phytoplankton under the conditions of climate change and the application of new remote-sensing methods. With the development of new remote-sensing technology and the expansion of phytoplankton research, future research should focus on (1) accurate observation of phytoplankton blooms; (2) the traits of phytoplankton blooms; and (3) the drivers, early warning, and management of phytoplankton blooms. In addition, we discuss the future challenges and opportunities in the use of remote sensing in phytoplankton blooms. Our review will promote a deeper and wider understanding of the field. [ABSTRACT FROM AUTHOR]

The interaction and adsorption of NO x (x = 1 , 2) gas molecules on the Al(111) surface were investigated by the density functional theory (DFT) method. The adsorption structures, energies, charge transfer, and density of states (DOS) of the adsorbed NO, NO2 on the Al(111) were studied. The O, O ′ -bridge NO 2 ∗ and the N, O-hcp NO* configurations are the most stable configurations of all the adsorption structures. The Bader charge analysis indicates that both NO2 and NO adsorption are accompanied by a back-donation from the top layer Al atoms to the adsorbates. The DOS of the adsorption structures shows that the σ orbitals (NO 2) and the π orbitals (NO) are available for accepting electron density. All these suggest that a strong interaction exists between the Al surface and the NO x (x = 1 , 2). Furthermore, NO2 decomposes into NO and O with the further dissociating into N and O on Al(111), which is thermodynamic favorable and kinetics feasible. [ABSTRACT FROM AUTHOR]

Additive manufacturing has many advantages in creating highly complex customized structures. In this study, a low‐cost multiscale stereolithography technology that can print a macroscale object with microscale surface structures with high throughput is demonstrated. The developed multiscale stereolithography is realized by dynamic switching of laser spot size and adaptively sliced layer thickness. An optical filter based on subwavelength resonance grating is used to modify laser spot size for lasers with different wavelengths and achieves a maximum resolution of 37 µm. The multiscale stereolithography process has 4.4× throughput improvement compared with the traditional stereolithography process with a single laser spot. For proof‐of‐concept testing, artificial shark skins with microriblet features are designed and 3D printed. In pipe flow experiments, the 3D printed shark skin demonstrates almost 10% average fluid drag reduction. Artificial lotus leaf surfaces are also 3D printed to demonstrate superhydrophobic property. This new process has the potential to serve as a powerful tool that can bring bioinspired structures into real‐life applications. [ABSTRACT FROM AUTHOR]

Ratooning rice is an essential rice-planting method. However, mechanical harvesting of the primary rice crop, while increasing efficiency, can negatively affect the yield of ratooning rice. Therefore, it is crucial to find ways to improve the grain yield of ratooning rice after the mechanical harvest of the primary rice. A two-year field experiment was conducted; the grain yield of ratooning rice was assessed by stubble righting after mechanical harvesting of primary rice. The study used two popular rice cultivars, YLiangyou911 and Kenliangyou801, as experimental materials. The experimental treatments included three groups: one without righting after rolling rice stubble (CK), another with mechanized righting after rolling rice stubble (T1), and a third one without rolling rice stubble by the machine (T2). The results of the study demonstrate that stubble righting after the mechanical harvest of primary rice (T1) had a substantial impact on the grain yield of ratooning rice. It led to grain yields similar to ratooning rice without mechanical rolling of the rice stubble (T2) and significantly outperformed the treatment without stubble righting after the mechanical harvest of primary rice (CK). The study observed significant effects of the year of the experiment (Y), the treatment applied (T), and the interaction between year and treatment (Y×T) on grain yield. Additionally, the treatment showed a significant influence on the yield components. Specifically, in 2021, the T1 and T2 treatments showed remarkable grain yield increases in YLiangyou911 by 107.41% and 147.97%, respectively, compared to CK. For Kenliangyou801 in 2021, the T1 and T2 treatments also resulted in notable improvements in grain yield by 45.85% and 114.26%, respectively. Similarly, in 2022, the grain yield increased by 6.99% for T1 and 23.87% for T2 in YLiangyou911, and by 77.23% for T1 and 187.13% for T2 in Kenliangyou801, compared to CK. The study also detected enhancements in several aspects, including biomass accumulation, solar radiation and photosynthetic characteristics, antioxidant response and nitrogen metabolism, and bud-regeneration capacity due to T1 and T2 treatments. Furthermore, correlation analysis was conducted to assess the relationship between grain yield and the investigated parameters. In conclusion, stubble righting after the mechanical harvest of primary rice resulted in significantly improved grain yield for ratooning rice. This improvement can be attributed to enhanced biomass accumulation, solar radiation and photosynthetic characteristics, antioxidant response and nitrogen metabolism, and increased bud-regeneration capacity. [ABSTRACT FROM AUTHOR]

A silver/silver molybdate (Ag/Ag2MoO4) composite was successfully synthesized through in situ reduction of Ag2MoO4 using NaBH4 at room temperature and characterized by various analytical techniques. The photocatalytic activity of the composite was evaluated by the degradation of the colorless antibiotic agent ciprofloxacin (CIP) under visible light irradiation. The experimental results indicated that the as-fabricated Ag/Ag2MoO4 composite showed greatly enhanced photocatalytic performance compared with pure Ag2MoO4, and exhibited high photodegradation efficiency with 99.5% removal of CIP in 60 min and excellent stability in five consecutive cycles. The improved photocatalytic performance could be mainly attributed to the surface plasmon resonance (SPR) effect of the Ag nanoparticles in the region of visible light. The active species trapping experiments and ESR analysis suggested that ṖOH and h+ were the main active species for the photocatalytic degradation. Eventually, a possible photocatalytic mechanism was proposed. [ABSTRACT FROM AUTHOR]

The g-C 3 N 4 /BiOCl 0.5 I 0.5 dual-Z-scheme heterojunction was prepared by microwave hydrothermal method to improve its photocatalytic CO 2 reduction and RhB degradation. The tight interface between BiOCl, BiOI and g-C 3 N 4 facilitates the rapid separation and transfer of photoinduced e-/h+ pairs, and the narrow bandgap was suitable for visible light trapping. BiO-CN2 showed better performance when the content of g-C 3 N 4 was 7 wt%, and the degradation of Rhodamine B (RhB 80 mg·L−1) by BiO-CN2 reached 92.32 % in 120 min. BiO-CN2 sample showed the highest CO yield (15.26 μmol g−1 h−1) under solar light irradiation. After five cycles, photo-corrosion led to mild inactivation of BiO-CN2 during sunlight-driven CO 2 reduction and degradation of RhB. [Display omitted] • BiO-CN2 had excellent photo-degradation for RhB and CO 2 reduction activity. • Dual-Z-scheme heterojunction junction favored the rapid transfer and separation of charge carriers. • BiO-CN2 (1.89 eV) had narrow band-gap structure for visible-light harvesting. [ABSTRACT FROM AUTHOR]

The g-C 3 N 4 /BiOCl 0.5 I 0.5 dual-Z-scheme heterojunction was prepared by microwave hydrothermal method to improve its photocatalytic CO 2 reduction and RhB degradation. The tight interface between BiOCl, BiOI and g-C 3 N 4 facilitates the rapid separation and transfer of photoinduced e-/h+ pairs, and the narrow bandgap was suitable for visible light trapping. BiO-CN2 showed better performance when the content of g-C 3 N 4 was 7 wt%, and the degradation of Rhodamine B (RhB 80 mg·L−1) by BiO-CN2 reached 92.32 % in 120 min. BiO-CN2 sample showed the highest CO yield (15.26 μmol g−1 h−1) under solar light irradiation. After five cycles, photo-corrosion led to mild inactivation of BiO-CN2 during sunlight-driven CO 2 reduction and degradation of RhB. [Display omitted] • BiO-CN2 had excellent photo-degradation for RhB and CO 2 reduction activity. • Dual-Z-scheme heterojunction junction favored the rapid transfer and separation of charge carriers. • BiO-CN2 (1.89 eV) had narrow band-gap structure for visible-light harvesting. [ABSTRACT FROM AUTHOR]

Great enthusiasm in nitrogen reduction reaction (NRR) towards the robust design of efficient catalysts is being stimulated by a promising active moiety featured by metal-N x , yet tackling the activity and selectivity dilemmas remains one of the most urgent and challenging tasks. Herein, based on a self-doping strategy and first-principles calculations, an emerging and stable graphitic carbon nitride, g-C 13 N 15 , is rationally proposed for the first time, and TM@g-C 13 N 15 (TM = from Ti to Au) single-atom catalysts benefiting from delocalized π−π conjugated interactions between substituted C 3 N 3 rings toward NRR are constructed. High-throughput "Four-Step" screening strategy helps Re@g-C 13 N 15 stand out from 23 TM-centers quickly since the binding strength of the target *N 2 H and *NH 2 adsorbates can be manipulated by Re to compromise. First-principles calculations reveal that Re@g-C 13 N 15 possesses satisfactory selectivity and impressively, miserly energy consumption with a low limiting potential of −0.20/-0.31 V for side-on/end-on N 2 -adsorption. Also, good thermodynamic stability, large Re-diffusion barrier, outstanding electrochemical durability, and facile synthesis for Re@g-C 13 N 15 ensure its implementations in ambient conditions. Particularly, good linear relationships between descriptors (ICOHP, Bader charge, bond length, d-band center, and spin moment) are established to describe/explain intrinsic activity trends/mechanism, bridging the relation between the intrinsic property and activity. [Display omitted] • Self-doping strategy and first-principles calculations are performed. • g-C 13 N 15 was rationally proposed for the first time. • Re@g-C 13 N 15 stands out from 23 TM-centers. • Good linear relationships were established to describe activity trends. • A full picture for TM@g-C 13 N 15 as high-performance NRR SACs was formed. [ABSTRACT FROM AUTHOR]

In response to the high cost of magnesium phosphate cement (MPC), due to the high production energy consumption of raw material MgO (sintering at 1600 °C for 5 h), and the requirement of adding retarders during the preparation process, we proposed using common elements B, Li, Na, K, and Cl in salt lakes to promote the sintering performance of MgO. We subsequently studied the preparation technology of low-activity MgO obtained from the pyrolysis of bischofite in salt lakes and low-temperature sintering (≤ 1200 °C). The migration law of coexisting elements and low-temperature sintering mechanism of salt lake bischofite was revealed during pyrolysis and low-temperature sintering, expanding the utilization path of salt lake bischofite and promoting resource recycling. We simultaneously developed a preparation technology for low-activity MgO used as raw MPC material, avoiding the use of retarders and reducing the raw material costs in the preparation of MPC. The results showed that coexisting elements migration was present in four different types of processes during the sintering process. Octahedral particles with a preferred orientation and exposed MgO (111) crystal face were obtained. With increased sintering temperature and time, the content and particle size of MgO increased and the specific surface area and porosity decreased, which led to the prolonged neutralization reaction time, as well as increased sintering degree and decrease in hydration activity. The formation of the liquid phase by bischofite and its coexisting elements was the key to MgO sintered at 1000 °C. [Display omitted] • The behavior of sintering MgO powder from bischofite in salt lake was studied. • After low-temperature and short-term sintering, bischofite could not be completely decomposed. • As the sintering temperature and time increased, the mass fraction of MgO in SM increased. • The coexisting elements exhibited different migration patterns during the sintering process. • The sintering temperature for preparing low-activity magnesium oxide was reduced. [ABSTRACT FROM AUTHOR]

High energy consumption and lack of readability under bright sunlight of conventional transmissive display technology greatly limit the user experience of mobile and wearable devices. To solve this issue, a hybrid display by overlaying a full‐color reflective display on top of a transmissive display is invented. The key component of this technology is a full‐color reflective display based on tandem switchable all‐dielectric metasurfaces. The switchable all‐dielectric metasurfaces in large size (average area ≈5 cm2) are invented and fabricated by low‐cost and high‐throughput nanoimprint lithography. Each switchable metasurface is formed by an array of TiO2/SiO2 hybrid nanopillars on top of a SiO2 substrate, which could reflect a unique color (blue, green, or red) light with high efficiency (bandwidth ≈100 nm and reflectance ≈80%). They become highly transparent (switched‐off) upon high‐index liquid injection. These metasurfaces demonstrate great characteristics such as polarization independence, large viewing angle (up to 60°), and ultra‐high resolution (over 6000 pixels per inch). This kind of full‐color reflective display can be combined with traditional transmissive display to achieve a low‐power hybrid display that performs well from totally dark to bright sunlight conditions. That resolves one of the biggest challenges in mobile and wearable device industry. [ABSTRACT FROM AUTHOR]

Customer demands for quieter centrifugal fans in the industry have brought their noise to the forefront. It is found that dipole sources on the surfaces of the rotating impeller and volute are the main acoustic noise sources. The volute effect is seen to have a significant influence on the radiation characters of the fan, although this is frequently ignored by previous studies. Hence, the indirect boundary element method (IBEM) is employed to study the noise of an industrial forward-curved centrifugal fan and to take the effect of volute reflection and scattering of the sound wave into consideration. A large eddy simulation (LES) is used to gain reliable pressure fluctuations on the surfaces of volute and rotating blades. Then the FW-H equation and Lowson equation are applied to calculate the dipole sources on the surfaces of the volute and the blades respectively. The predicted aerodynamic noise of the fan with and without the volute is compared to experiment. The results indicate that the pressure fluctuations on the volute surfaces, especially on the tongue surface, are the main dipole source. It is also found that the application of IBEM can improve the prediction accuracy greatly, especially for the blade passing frequency and its higher harmonics. [ABSTRACT FROM AUTHOR]

• A cascading path from lake features to water surface DOM and CH 4 contents was built. • Lake morphology had a great direct negative effect on CH 4 and indirect effects on DOM. • Geoclimatic condition impacted DOM and CH 4 by affecting land use and physical factors. • Land use affected DOM and CH 4 via changing water quality and then aquatic biota. • Phytoplankton and macroinvertebrates impacted DOM and CH 4 in different patterns. Many factors have been reported to affect material cycling in lakes, but the combined and cascading impacts of external environmental factors and in-lake biota on lake carbon cycling are poorly understood. We elucidated the influencing pathways of geoclimatic factors, lake morphometry, land-use type, chemical and physical factors, and biological taxa (phytoplankton and macroinvertebrates) on the concentrations of two important components of carbon cycling, i.e., dissolved organic matter (DOM) and methane (CH 4) based on datasets from 64 plateau lakes in Southwest China. Partial least squares path modelling (PLS-PM) indicated that (1) geoclimatic factors influenced DOM and CH 4 by affecting land use and lake physical factors (e.g., water temperature), (2) lake morphometry (water depth and lake area) had a direct and great negative effect on the CH 4 concentration related to the production and oxidation of CH 4 and affected phytoplankton and macroinvertebrates by influencing chemical and physical factors, (3) land-use type affected DOM and CH 4 concentrations in both direct and indirect ways, (4) terrestrial humic-like DOM was mainly discharged from forestland and also affected by macroinvertebrates, while the impacts of agricultural and construction land on autochthonous DOM and CH 4 concentrations mainly occurred by changing nutrients and then the aquatic biota. Moreover, changes in aquatic biota, primarily affected by water quality, influenced DOM spectral properties, and the two biotas affected DOM and CH 4 concentrations differently. Phytoplankton, especially cyanobacteria contributed to (protein-like and humic-like) DOM in both direct and indirect ways related to eutrophication, whereas macroinvertebrates influenced DOM possibly by utilization, bioturbation, and microbial decomposition of feces according to their different relationships with DOM spectral indices. Additionally, CH 4 production can be enhanced by DOM accumulation, and the significant positive correlations of CH 4 concentrations with protein-like DOM and biological index indicate that autochthonous DOM may play an important role for the CH 4 production. Our findings contribute to the understanding of lake carbon cycling under natural conditions and anthropogenic disturbances. Graphical Abstract [Display omitted]. [ABSTRACT FROM AUTHOR]

Nanoimprint lithography is a promising technology for patterning large-area structures in nanometer scale at a low cost. In order to fabricate large-area nanoimprint master mold, interference lithography is widely used in defining periodical structures. However, neither roughness nor structural dimension can be effectively controlled via interference exposure. In this paper, we report a fabrication technique based on V-shaped master mold that can adjust line width of gratings as well as reduce the sidewall roughness. The fabrication of the V-shaped grating master mold is demonstrated, and the line width tuning and smoothening processes are discussed. With the help of the smoothening process, the optical efficiency of smoothened guided-mode resonance grating increased by 75 % from the original sample. [ABSTRACT FROM AUTHOR]

Nanoimprint lithography (NIL) is an indispensable tool to realize a fast and accurate nanoscale patterning in nanophotonics due to high resolution and high yield. The number of publication on NIL has increased from less than a hundred per year to over three thousand per year. In this paper, the most recent developments on NIL patterning transfer processes and its applications on nanophotonics are discussed and reviewed. NIL has been opening up new opportunities for nanophotonics, especially in fabricating optical meta-materials. With more researches on this low-cost high-throughput fabrication technology, we should anticipate a brighter future for nanophotonics and NIL. [ABSTRACT FROM AUTHOR]