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We investigate the robust chance constrained optimization problem (RCCOP), which is a combination of the distributionally robust optimization (DRO) and the chance constraint (CC). The RCCOP plays an important role in modeling uncertain parameters within a decision-making framework. The chance constraint, which is equivalent to a constraint of Value-at-risk (VaR), is approximated by risk measures such as Entropic Value-at-risk (EVaR) or Conditional Value-at-risk (CVaR) due to its difficulty to be evaluated. An excellent approximation requires both tractability and non-conservativeness. In addition, the DRO assumes that we know partial information about the distribution of uncertain parameters instead of their known true underlying probability distribution. In this article, we develop a novel approximation EVaR- PC based on EVaR for CC. Then, we evaluate the proposed approximation EVaR- PC using a discrepancy-based ambiguity set with the wasserstein distance. From a theoretical perspective, the EVaR- PC is less conservative than EVaR and the wasserstein distance possesses many good theoretical properties; from a practical perspective, the discrepancy-based ambiguity set can make full use of the data to estimate the nominal distribution and reduce the sensitivity of decisions to priori knowledges. To show the advantages of our method, we show its application in portfolio management in detail and give the relevant experimental results. [ABSTRACT FROM AUTHOR]

Purpose: A systematic review of randomized controlled trials (RCTs) was conducted to assess the potential effect of therapeutic massage/Tuina on functional dyspepsia (FD) patients. Method: Twelve databases and three clinical trial registries were searched until December 2021, for RCTs that compared Tuina combined with or without conventional therapy versus conventional therapy in FD. We assessed the methodological quality of included trials by the Cochrane Risk of Bias tool, and graded the quality of the evidence. The data were presented as risk ratio (RR) or mean difference (MD) respectively with their 95% confidence interval (CI). Results: In total, 14 RCTs with 1128 FD participants were included. Compared with conventional therapy, Tuina showed significant beneficial effects on improving overall symptom (RR = 1.12, 95% CI 1.06 to 1.19, low certainty evidence), and early satiation (MD −0.44 scores, 95% CI −0.72 to −0.16, very low certainty evidence). Compared with conventional therapy, Tuina plus conventional therapy also significantly improved overall symptom (RR = 1.14, 95% CI 1.06–1.23, low certainty evidence), quality of life (MD 10.44 scores, 95% CI 7.65–13.23, low certainty evidence), and epigastric pain (MD −0.76 scores, 95% CI −1.11 to −0.41, low certainty evidence). No adverse events related to Tuina and cost-effectiveness were reported. Conclusion: Low certainty evidence showed that Tuina significantly improved overall symptom of FD participants compared with conventional therapy. Low certainty evidence showed that Tuina plus conventional therapy obviously improved overall symptom and quality of life of FD participants compared with conventional therapy. [ABSTRACT FROM AUTHOR]

In order to solve the problem of environmental health hazards caused by phthalate esters, a series of pure Bi2O2CO3 and light (La, Ce, Pr, Nd, Sm and Eu) and heavy (Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu) rare earth-doped Bi2O2CO3 samples were prepared by hydrothermal method. The crystalline phase composition and physical structure of the samples calcined at 300 °C were studied, and we found that the rare earth ion doping promoted the transformation of Bi2O2CO3 to β-Bi2O3 crystalline phase, thus obtaining a mixed crystal phase photocatalyst constituted by rare earth-ion-doped Bi2O2CO3/β-Bi2O3. The Bi2O3/Bi2O2CO3 heterostructure had a lower band gap and more efficient charge transfer. The fabricated samples were applied to the photocatalytic degradation of dimethyl phthalate (DMP) under a 300 W tungsten lamp, and it was found that the rare earth ion doping enhanced the photocatalytic degradation activity of DMP, in which the heavy rare earth of Er-doped sample reached 78% degradation for DMP at 150 min of light illumination. In addition, the doping of rare earths resulted in a larger specific surface area and a stronger absorption of visible light. At the same time, the formation of Bi2O2CO3/β-Bi2O3 heterogeneous junction enhanced the separation efficiency of photogenerated electrons and holes. [ABSTRACT FROM AUTHOR]

Interfacial engineering of perovskite films has been the main strategies in improving the efficiency and stability of perovskite solar cells (PSCs). In this study, three new donor‐acceptor (D–A)‐type interfacial dipole (DAID) molecules with hole‐transporting and different anchoring units are designed and employed in PSCs. The formation of interface dipoles by the DAID molecules on the perovskite film can efficiently modulate the energy level alignment, improve charge extraction, and reduce non‐radiative recombination. Among the three DAID molecules, TPA‐BAM with amide group exhibits the best chemical and optoelectrical properties, achieving a champion PCE of 25.29 % with the enhanced open‐circuit voltage of 1.174 V and fill factor of 84.34 %, due to the reduced defect density and improved interfacial hole extraction. Meanwhile, the operational stability of the unencapsulated device has been significantly improved. Our study provides a prospect for rationalized screening of interfacial dipole materials for efficient and stable PSCs. [ABSTRACT FROM AUTHOR]

The objective of this study is to summarize the effects of surfactants on anaerobic digestion (AD) of waste activated sludge (WAS). The increasing amount of WAS has caused serious environmental problems. Anaerobic digestion, as the main treatment for WAS containing three stages (i.e. hydrolysis, acidogenesis, and methanogenesis), has been widely investigated. Surfactant addition has been demonstrated to improve the efficiency of AD. Surfactant, as an amphipathic substance, can enhance the efficiency of hydrolysis by separating large sludge and releasing the encapsulated hydrolase, providing more substance for subsequent acidogenesis. Afterwards, the short chain fatty acids (SCFAs), as the major product, have been produced. Previous investigations revealed that surfactant could affect the transformation of SCFA. They changed the types of acidification products by promoting changes in microbial activity and in the ratio of carbon to nitrogen (C/N), especially the ratio of acetic and propionic acid, which were applied for either the removal of nutrient or the production of polyhydroxyalkanoate (PHA). In addition, the activity of microorganisms can be affected by surfactant, which mainly leads to the activity changes of methanogens. Besides, the solubilization of surfactant will promote the solubility of contaminants in sludge, such as organic contaminants and heavy metals, by increasing the bioavailability or desorbing of the sludge. [ABSTRACT FROM AUTHOR]

Social development is accompanied by technological progress, which commonly leads to the expansion of pollution As an essential resource of modern medical treatment, antibiotics have become a hot topic in the aspect of environmental pollution. In this study, we first used fish scales to synthesize N, P-codoped biochar catalyst (FS-BC) as peroxymonosulfate (PMS) and peroxydisulfate (PDS) activator to degrade tetracycline hydrochloride (TC). At the same time, peanut shell biochar (PS-BC) and coffee ground biochar (CG-BC) were prepared as reference materials. Among them, FS-BC exhibited the best catalytic performance due to the excellent defect structure (I D /I G = 1.225) and the synergism of N, P heteroatoms. PS-BC, FS-BC and CG-BC achieved degradation efficiencies of 86.26%, 99.71% and 84.41% for TC during PMS activation and 56.79%, 93.99% and 49.12% during PDS, respectively. In both FS-BC/PMS and FS-BC/PDS systems, non-free radical pathways involved singlet oxygen (1O 2), surface-bound radicals mechanism and direct electron transfer mechanism. Structural defects, graphitic N and pyridinic N, P–C groups and positively charged sp 2 hybridized C adjacent to graphitic N were all critical active sites. FS-BC has the potential for practical applications and development because of its robust adaptation to pH and anions and stable re-usability. This study not only provides a reference for biochar selection, but also suggests a superior strategy for TC degradation in the environment. [Display omitted] • SynThesis of a novel N, P co-doped fish scale biochar catalyst. • The degradation efficiency of TC can reach 99.71% in FS-BC/PMS system. • Differences in the activation mechanism of FS-BC on PMS and PDS do not appear. • The activation mechanism only involved non-free radical mechanism. [ABSTRACT FROM AUTHOR]

[Display omitted] • A new photocatalytic material was forming by self-assembling of V-doped BiOIO 3 and FTCN and introducing of tungsten carbide. • V-BiOIO 3 /g-C 3 N 4 /WC have exhibited high visible-light photodegradation of antibiotic. • The presence of S-type Schottky heterojunction in V-BiOIO 3 /g-C 3 N 4 /WC enhances the degradation efficiency of tetracycline. • Tungsten carbide as a cheap and widely available material has a positive effect on the promotion of photocatalytic industrial process. A novel Schottky heterojunction was obtained by co-calcining fish-scale tubular carbon nitride (FTCN), V-BiOIO 3 and Tungsten carbide (WC) for photocatalytic degradation of tetracycline hydrochloride (TCH). The novel Schottky heterojunction has been analyzed by several characterizations and experiments. The case of photocatalytic degradation was studied for different initial concentrations, electrolyte and pH, respectively. The experiments have indicated that the V-BiOIO 3 /g-C 3 N 4 /WC performed an excellent activity of photocatalytic for TCH degradation (89.0%). In the mechanism analysis, we first deduce that the V-BiO3/FTCN compound belongs to the S-scheme heterojunction photocatalysts based on the properties of the band gap structure, which can effectively suppress recombination of joint carriers. Secondly, the introduction of the cocatalyst WC formed Schottky junction, which could play a role as an electronic library to trap e− and promote the separation of photo-induced carrier and thus maximize the strong oxidation ability of h+. In addition, the introduction of WC could also significantly enhance the optical absorption properties of the composites. This research could provide a new idea for the construction of novel and efficient carbon nitride-based photocatalysts under VSL (visible light), and promote its practical application in environmental remediation. [ABSTRACT FROM AUTHOR]

In fusion liquid metal blanket, sudden expansions and sudden contractions are very common geometries. Changing of the cross-section causes 3-D magnetohydrodynamic (MHD) effects, which will affect the flow pattern, current distribution and pressure drop. In this paper the numerical code based on OpenFOAM platform developed by University of Science and Technology of China was used to investigate and optimize the sudden expansion pipe. The code has been validated by the recommended benchmark cases including Shercliff, Hunt, ALEX experiments (rectangular duct and round pipe) and KIT experiment cases. The obtained numerical results agreed well with those of all the benchmark cases. Previous and valuable analytical and experimental works have been done by L. Buhler, et. el. Based on these works, in the present paper, further investigation of different expansion lengths between the upstream pipe and downstream pipe at high Hartmann number and Reynolds number were conducted. Besides, different expansion ratios with a specific expansion length were conducted. The numerical results showed that with the increasing of expansion length, the 3D MHD effects gradually weakened. Especially, the 3D pressure drop decreases with the increasing of expansion length. Whereas, the expansion ratio factor shows no obvious influences on the total MHD pressure drop but greatly influence the local pressure distribution. These numerical simulations can be used to evaluate the MHD flow inside the expansion and contraction pipes. [ABSTRACT FROM AUTHOR]

Liquid metal flow in rectangular bends is a common phenomenon of fusion liquid metal blanket operation, in which the velocity distributions and magnetohydrodynamic (MHD) pressure drop are considered as critical issues. Previous studies mainly aimed at specific fixed geometry for bend flows in LM blanket. The present investigation focuses on numerical analysis of MHD flow in 3D rectangular bends at laminar conditions, which is aimed to reduce MHD pressure drop caused by electromagnetic coupling in conductive flow, especially in bend corner region. The used code has been developed by University of Science and Technology of China (USTC) and validated by recommended benchmark cases such as Shercliff, ALEX experiments and KIT experiment cases, etc. In order to search the optimal duct bending, certain parameters such as different aspect ratio of the duct corner area cross-section, distance of import and export from the elbow and wall conductance ratio have been considered to investigate the pressure drop of MHD flow. Moreover, the effects of different magnetic field direction relative to flow distribution between bends have also been analyzed. [ABSTRACT FROM AUTHOR]

The concept of dual coolant liquid metal (LM) blanket has been proposed in different countries to demonstrate the technical feasibility of DEMO reactor. In the system, helium gas and PbLi eutectic, separated by structure grid, are used to cool main structure materials and to be self-cooled, respectively. The non-uniform wall thickness of structure materials gives rise to wall non-homogeneous conductance ratio. It will lead to electric current distribution changes, resulting in significant changes in the velocity distribution and pressure drop of magnetohydrodynamic (MHD) flows. In order to investigate the effect of helium channels on MHD flows, different methods of numerical simulations cases are carried out including the cases of different wall thicknesses, single pass of helium cooling channels, and three types of dual helium cooling channels. The results showed that helium tubes are able to affect the velocity distribution in the boundary layer by forming wave sharp which transfers from Hartmann boundary layer to the core area. In addition, the potential profile and pressure drop in the cases have been compared to these in the case of walls without cooling channel, and the pressure gradient of a simplified single short duct MHD flow in blanket shows small waver along the central axis in the helium channel position. [ABSTRACT FROM AUTHOR]

The pressure-implicit with splitting of operators (PISO) magnetohydrodynamics MHD solver of the couple of Navier–Stokes equations and Maxwell equations was implemented on Kepler-class graphics processing units (GPUs) using the CUDA technology. The solver is developed on open source code OpenFOAM based on consistent and conservative scheme which is suitable for simulating MHD flow under strong magnetic field in fusion liquid metal blanket with structured or unstructured mesh. We verified the validity of the implementation on several standard cases including the benchmark I of Shercliff and Hunt's cases, benchmark II of fully developed circular pipe MHD flow cases and benchmark III of KIT experimental case. Computational performance of the GPU implementation was examined by comparing its double precision run times with those of essentially the same algorithms and meshes. The resulted showed that a GPU (GTX 770) can outperform a server-class 4-core, 8-thread CPU (Intel Core i7-4770k) by a factor of 2 at least. [ABSTRACT FROM AUTHOR]

Introduction: Pancreatic follicular dendritic cell sarcoma (FDCS) is an exceptionally rare and low-to-moderate malignancy, with only seven reported cases to date. Clinical diagnosis of FDCS is challenging due to the lack of distinct biological and radiographic features. Case presentation: A 67-year-old woman presented to the hospital with a 4-day history of severe abdominal pain. Imaging studies (CT and MRI) revealed a large cystic mass located at the tail of the pancreas, which was suspected to be myeloid sarcoma (MS) based on EUS and CT-guided pancreatic puncture. Postoperative pathology and immunohistochemistry confirmed the diagnosis of pancreatic FDCS. After the diagnosis was confirmed, the patient received postoperative chemotherapy with the CHOP regimen. At 11 months of follow-up, there was no evidence of recurrence. Seven published cases have been reviewed to comprehensively summarize the clinical characteristics, diagnosis, and treatment options of FDCS. Conclusion: While imaging can be useful in detecting pancreatic FDCS, it should be interpreted with caution as it can be challenging to differentiate from other pancreatic tumors. Pathology and immunohistochemistry are considered the gold standard for diagnosis, with CD21, CD23, and CD35 being specific tumor cell markers. However, preoperative diagnosis of pancreatic FDCS remains difficult, and the pancreatic puncture may further increase the risk of misdiagnosis. The disease is highly prone to recurrence and metastasis, and surgery is the preferred method for both diagnosis and treatment of localized disease. [ABSTRACT FROM AUTHOR]

A highly nitrogen-deficient g-C3N4 (AH-CN) nanosheet material was successfully prepared via an acetaldehyde-assisted hydrothermal route. The as-prepared AH-CN material was analyzed by X-ray powder diffraction (XRD), N2 physical adsorption–desorption, scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), photoluminescence (PL), Fourier transform infrared (FT-IR) spectroscopy, UV–vis diffuse reflectance spectroscopy (UV-Vis DRS), elemental analysis (EA), electron paramagnetic resonance (EPR) and photoelectric tests. Compared with H-CN (g-C3N4 treated hydrothermally without acetaldehyde), a large number of nitrogen vacancies were produced over AH-CN (g-C3N4 treated under acetaldehyde-assisted hydrothermal conditions). The bandgap of AH-CN decreases and its light absorption was largely improved in UV and visible light regions. Moreover, the as-prepared material possesses a low recombination rate of photogenerated carriers and a relatively negative conduction band potential over AH-CN, which contributes to its strong photocatalytic reduction ability. Under simulated sunlight illumination, the photocatalytic performance for H2O2 production and Cr(VI) reduction of the AH-CN material was evaluated. The highest H2O2 yield of 670 μM was obtained over 50AH-CN, which was 2.6 times that of g-CN. In the removal of Cr(VI) via reduction, the removal rate of Cr(VI) over 50AH-CN reaches 56% which is about 5.6 times that of g-CN. [ABSTRACT FROM AUTHOR]

Morphology adjustment is a feasible method to change the physicochemical properties of photocatalysts. The issue that excessively thick tube wall of tubular g-C 3 N 4 is not conducive to the electron migration from inside to the surface thus inhibiting the separation of photogenerated carriers has always been ignored. Potassium ions were used to regulate the structure of the tubular supramolecular precursor by breaking hydrogen bonds, thereby promoting the synthesis of delaminated laminar tubular g-C 3 N 4 (K-CN), which not only shortened the transfer distance of photogenerated electrons but also provided abundant reaction active sites. Experiments and DFT calculations were combined to reveal the details of the physicochemical properties of K-CN. The photocatalytic capacity of K-CN for tetracycline hydrochloride (TCH) degradation and H 2 O 2 generation were 83% and 133 μM, respectively. This work not only synthesized a novel delaminated tubular g-C 3 N 4 but also provided a strategy and inspiration for structure and performance optimization for tubular g-C 3 N 4. [Display omitted] • Supramolecular self-assembly produced tubular g-C 3 N 4 precursors. • Potassium ions was influenced on the supramolecular self-assembly. • Destruction of the hydrogen bond induced delamination of tubular g-C 3 N 4. • Experiment and DFT calculation were combined to reveal the properties of K-CN. • Delamination promoted K-CN showed strong photocatalytic activity. [ABSTRACT FROM AUTHOR]

Morphology adjustment is a feasible method to change the physicochemical properties of photocatalysts. The issue that excessively thick tube wall of tubular g-C 3 N 4 is not conducive to the electron migration from inside to the surface thus inhibiting the separation of photogenerated carriers has always been ignored. Potassium ions were used to regulate the structure of the tubular supramolecular precursor by breaking hydrogen bonds, thereby promoting the synthesis of delaminated laminar tubular g-C 3 N 4 (K-CN), which not only shortened the transfer distance of photogenerated electrons but also provided abundant reaction active sites. Experiments and DFT calculations were combined to reveal the details of the physicochemical properties of K-CN. The photocatalytic capacity of K-CN for tetracycline hydrochloride (TCH) degradation and H 2 O 2 generation were 83% and 133 μM, respectively. This work not only synthesized a novel delaminated tubular g-C 3 N 4 but also provided a strategy and inspiration for structure and performance optimization for tubular g-C 3 N 4. [Display omitted] • Supramolecular self-assembly produced tubular g-C 3 N 4 precursors. • Potassium ions was influenced on the supramolecular self-assembly. • Destruction of the hydrogen bond induced delamination of tubular g-C 3 N 4. • Experiment and DFT calculation were combined to reveal the properties of K-CN. • Delamination promoted K-CN showed strong photocatalytic activity. [ABSTRACT FROM AUTHOR]

• HPSs@PVB films were successfully prepared. • HPSs possess superior optical performance after PVB coating. • The thermal cyclability, water and UV resistance of HPSs@PVB films are excellent. • The color gamut is as wide as 126% based on the high color purity HPSs@PVB device, reaching 94% of Rec. 2020. Here, polyvinyl butyral (PVB) films-protected CsPbBr 3 /Cs 4 PbBr 6 halide perovskite solids (HPSs) were successfully synthesized. The optical properties and structure of HPSs@PVB were studied, finding the photoluminescence quantum yields (PLQYs) of this novel composite material is as high as 60.4%. More importantly, HPSs@PVB has excellent thermal cyclability, water and ultraviolet (UV) resistance. In addition, HPSs@PVB was further applied to light emitting diodes (LEDs) and displays. By combining green-emitting HPSs@PVB and red-emitting CsPbBrI 2 NCs@PVB with InGaN 460 nm blue chip, white light emitting diode (WLED) device can be successfully fabricated. And the device exhibits good stability and the color gamut is as wide as 126%, reaching 94% of Rec. 2020. This work proposes a simple approach to solve the challenging stability issue of perovskite nanocrystals (NCs), having a positive implication for their practical application in LEDs and display backlights. [ABSTRACT FROM AUTHOR]

• Gd-doped CsPbBrI 2 NCs were successfully prepared in borosilicate glass matrix. • CsPbBrI 2 NCs@glasses possess superior optical performance through Gd3+ doping. • The water / thermal / light stability of Gd-doped CsPbBrI 2 NCs@glasses are excellent. • High-performance WLEDs was assembled successfully by Gd-doped CsPbBrI 2 NCs@glasses. Here, Gd-doped CsPbBrI 2 nanocrystals (NCs) in borosilicate glass (B 2 O 3 -SiO 2 -ZnO) were successfully synthesized by the traditional melting quenching method. The optical properties of CsPbBrI 2 NCs@glasses at different heat treatment temperatures and the content of Gd3+ were studied. It is found that CsPbBrI 2 NCs@glasses have greatly improved photoluminescence quantum yields (PLQYs) after doping (form 15.3% to 37%) and excellent hydrothermal and light stability. In addition, a white light emitting diode (WLED) was successfully prepared by combining Gd-doped CsPbBrI 2 NCs@glass and Ce3+: YAG phosphors with the blue light emitting diode (LED). After a series of adjustments, the high performance WLED device with a chromaticity coordinate (CIE) of (0.3340, 0.3386), luminous efficiency (LE) of 90.09 lm/W, correlated color temperature (CCT) of 5430 K and the color rendering index (CRI) of 81.4 was fabricated. This work provides a new strategy in the field of metal ion doped perovskite NCs for future reference and has potential applications in LEDs. [ABSTRACT FROM AUTHOR]

In the pursuit of highly efficient perovskite solar cells, spiro‐OMeTAD has demonstrated recorded power conversion efficiencies (PCEs), however, the stability issue remains one of the bottlenecks constraining its commercial development. In this study, we successfully synthesize a novel self‐polymerized spiro‐type interfacial molecule, termed v‐spiro. The linearly arranged molecule exhibits stronger intermolecular interactions and higher intrinsic hole mobility compared to spiro‐OMeTAD. Importantly, the vinyl groups in v‐spiro enable in situ polymerization, forming a polymeric protective layer on the perovskite film surface, which proves highly effective in suppressing moisture degradation and ion migration. Utilizing these advantages, poly‐v‐spiro‐based device achieves an outstanding efficiency of 24.54 %, with an enhanced open‐circuit voltage of 1.173 V and a fill factor of 81.11 %, owing to the reduced defect density, energy level alignment and efficient interfacial hole extraction. Furthermore, the operational stability of unencapsulated devices is significantly enhanced, maintaining initial efficiencies above 90 % even after 2000 hours under approximately 60 % humidity or 1250 hours under continuous AM 1.5G sunlight exposure. This work presents a comprehensive approach to achieving both high efficiency and long‐term stability in PSCs through innovative interfacial design. [ABSTRACT FROM AUTHOR]

In the pursuit of highly efficient perovskite solar cells, spiro‐OMeTAD has demonstrated recorded power conversion efficiencies (PCEs), however, the stability issue remains one of the bottlenecks constraining its commercial development. In this study, we successfully synthesize a novel self‐polymerized spiro‐type interfacial molecule, termed v‐spiro. The linearly arranged molecule exhibits stronger intermolecular interactions and higher intrinsic hole mobility compared to spiro‐OMeTAD. Importantly, the vinyl groups in v‐spiro enable in situ polymerization, forming a polymeric protective layer on the perovskite film surface, which proves highly effective in suppressing moisture degradation and ion migration. Utilizing these advantages, poly‐v‐spiro‐based device achieves an outstanding efficiency of 24.54 %, with an enhanced open‐circuit voltage of 1.173 V and a fill factor of 81.11 %, owing to the reduced defect density, energy level alignment and efficient interfacial hole extraction. Furthermore, the operational stability of unencapsulated devices is significantly enhanced, maintaining initial efficiencies above 90 % even after 2000 hours under approximately 60 % humidity or 1250 hours under continuous AM 1.5G sunlight exposure. This work presents a comprehensive approach to achieving both high efficiency and long‐term stability in PSCs through innovative interfacial design. [ABSTRACT FROM AUTHOR]

The outbreak of COVID-19 has caused concerns globally. To reduce the rapid transmission of the virus, strict city lockdown measures were conducted in different regions. China is the country that takes the earliest home-based quarantine for people. Although normal industrial and social activities were suspended, the spread of virus was efficiently controlled. Simultaneously, another merit of the city lockdown measure was noticed, which is the improvement of the air quality. Contamination levels of multiple atmospheric pollutants were decreased. However, in this work, 24 and 14 air fine particulate matter (PM 2.5) samples were continuously collected before and during COVID-19 city lockdown in Linfen (a typical heavy industrial city in China), and intriguingly, the unreduced concentration was found for environmentally persistent free radicals (EPFRs) in PM 2.5 after normal life suspension. The primary non-stopped coal combustion source and secondary Cu-related atmospheric reaction may have impacts on this phenomenon. The cigarette-based assessment model also indicated possible exposure risks of PM 2.5 -bound EPFRs during lockdown of Linfen. This study revealed not all the contaminants in the atmosphere had an apparent concentration decrease during city lockdown, suggesting the pollutants with complicated sources and formation mechanisms, like EPFRs in PM 2.5 , still should not be ignored. [Display omitted] [ABSTRACT FROM AUTHOR]

Core–shell structures, where the "guest" material is encapsulated within a protective shell, integrate the advantages of different materials to enhance the overall properties of the composite. Covalent–organic frameworks (COFs) are favorable candidates for composing core–shell structures due to their inherent porosity, good activity, excellent stability, and other advantages. In particular, COFs as shells to encapsulate other functional materials are becoming increasingly popular in the fields of environmental remediation and energy conversion. However, there is a lack of reviews on COF‐based core–shell materials. In this context, this review provides a systematic summary of the current research on COF‐based core–shell composites. First, a simple classification is made for COF‐based core–shell composites. The second part of the review describes the main synthesis methods. The changes brought about by the COF shell and core–shell structures on the properties of the composites and their applications in photocatalysis, electrocatalysis, adsorption, sensing, and supercapacitors are then emphasized. Finally, new perspectives on the future development and challenges of composites are presented. The purpose of this study is to provide future insights into the design and application of COF‐based core–shell composites. [ABSTRACT FROM AUTHOR]

Abstract It is of great significance to timely, accurately, and effectively monitor land use/cover in city regions for the reasonable development and utilization of urban land resources. The remotely sensed dynamic monitoring of Land use/land cover (LULC) in rapidly developing city regions has increasingly depended on remote-sensing data at high temporal and spatial resolutions. However, due to the influence of revisiting periods and weather, it is difficult to acquire enough time-series images with high quality at both high temporal and spatial resolution from the same sensor. In this paper we used the temporal-spatial fusion model ESTARFM (Enhanced Spatial and Temporal Adaptive Reflectance Fusion Model) to blend Landsat8 and MODIS data and obtain time-series Landsat8 images. Then, land cover information is extracted using an object-based classification method. In this study, the proposed method is validated by a case study of the Changsha City. The results show that the overall accuracy and Kappa coefficient were 94.38% and 0.88, respectively, and the user/producer accuracies of vegetation types were all over 85%. Our approach provides an accurate and efficient technical method for the effective extraction of land use/cover information in the highly heterogeneous regions. [ABSTRACT FROM AUTHOR]

This paper constructs a comprehensive evaluation system of human settlements focusing on housing conditions, urban natural environments, social economy, and public infrastructure. Principal Component Analysis and Cluster Analysis are used to analyze and rank the 2003–2013 human settlements index and create five clusters for 35 major cities in China (including municipalities, provincial capitals, and Prefecture-level cities). On the basis of four years of a spatial analysis of the human settlements index, we find that living conditions of 35 Chinese cities have significantly improved; severe air pollution persists in China, with large differences between the north and the south; weak correlation between urban human settlements and the growth rate of economic development; and the infrastructure of China's mega cities is overloaded. The results confirm and quantify growing geographic disparities and deep structural urban challenges that are associated with rapid economic growth and social change, leaving many cities in China to struggle with worsening pollution, excessive demand on existing infrastructures, and housing prices that rise faster than disposable incomes. [ABSTRACT FROM AUTHOR]

[Display omitted] Mn and N co-doped biochar (Mn-N-TS) was prepared as an effective catalyst to activate peroxymonosulfate (PMS) for ciprofloxacin (CIP) degradation. As opposed to Mn-TS and N-TS, Mn-N-TS had more active sites containing N and Mn, as well as a greater specific surface area (923.733 m2 g−1). The Mn-N-TS exhibited excellent PMS activation ability. In the Mn-N-TS/PMS system, the CIP removal efficiency was 91.9% in 120 min. Mn and N co-doping could accelerate electron transfer between CIP and PMS molecules. Simultaneously, defect sites, graphitic N, pyridinic N, C═O groups, and Mn(II)/Mn(III)/Mn(IV) redox cycles acted as active sites to activate PMS and generate free radicals (OH, SO 4 − and 1O 2). Furthermore, the Mn-N-TS/PMS system could effectively degrade CIP in a wide pH range, background substances, and actual water. Finally, a probable mechanism of PMS activation by Mn-N-TS was proposed. In conclusion, this work gave a novel direction for the rational design of Mn and N co-doped biochar. [ABSTRACT FROM AUTHOR]

In fusion liquid metal blankets, complex geometries involving contractions, expansions, bends, manifolds are very common. The characteristics of liquid metal flow in these geometries are significant. In order to extend the magnetohydrodynamic (MHD) solver developed on OpenFOAM platform to be applied in the complex geometry, the MHD solver based on unstructured meshes has been implemented. The adoption of non-orthogonal correction techniques in the solver makes it possible to process the non-orthogonal meshes in complex geometries. The present paper focused on the validation of the code under critical conditions. An analytical solution benchmark case and two experimental benchmark cases were conducted to validate the code. Benchmark case I is MHD flow in a circular pipe with arbitrary electric conductivity of the walls in a uniform magnetic field. Benchmark cases II and III are experimental cases of 3D laminar steady MHD flow under fringing magnetic field. In all these cases, the numerical results match well with the benchmark cases. [ABSTRACT FROM AUTHOR]

In order to solve the problem of poor crack resistance and frost resistance of semi-rigid base, rubber powder and retarder were added to a semi-rigid base mixture. First, 61 mixing ratios were determined. Then, through the unconfined compressive strength, splitting strength, and other tests, the mechanical, crack, and frost resistance properties of the retarded composite semi-rigid base coarse mixture with rubber powder were studied. Finally, the macro and micro properties of the two kinds of admixture composite semi-rigid base coarse mixtures were studied by means of SEM and industrial CT. The results show that rubber powder and retarder can effectively improve the cracking and freezing resistance of the mixture. After five freeze–thaw cycle tests, the strength of the retarded composite semi-rigid base material mixed with rubber powder decreased slightly compared with the mixture without additives. It can be seen that rubber powder improved the frost resistance of the mixture. When the content of rubber powder was 1.5%, the BDR value of the mixture increased by 8.8%. With the increase of unconfined compressive strength, splitting strength, and flexural tensile strength at 28 d and 90 d, it was found that the retarder improved the middle and late strength of the mixture. When the content of retarder was 0.09%, the increase of unconfined compressive strength at 28 d reached 3.9%. The addition of rubber powder and retarder improved the distribution of internal pores, the proportion of large pores decreased, and the proportion of small pores increased. The retarder changed the morphology of hydration products, formed a dense network supporting structure, further refined the pores, and reduced the porosity of the mixture. The proportion of pores with a volume greater than 100 mm3 in the total pore volume decreased by 26.01%, and the proportion of medium pores increased by 13.07%, thereby improving the mechanical properties of the mixture. [ABSTRACT FROM AUTHOR]

• DMD effectively predicts the state transitions of core dynamics and xenon transients. • The impact of DMD parameters on prediction performance is investigated. • Detailed analysis of the 3-D LWR Core Transient Benchmark is performed. This study proposes a method based on Dynamic Mode Decomposition (DMD) for predicting the state transitions of core dynamics and xenon transients in nuclear reactors. Both types of transients, occurring at different time or spatial scales, have significant impacts on the stability and safety of nuclear reactors. The DMD method is employed to model and predict the transient behaviors in nuclear reactors. DMD is a data-driven model simplification technique that extracts the dynamic modes, i.e., characteristic patterns, from time-series data. By applying DMD to the data of core dynamics and xenon transients, we obtain the characteristic modes of the system under different states, which are then used for predicting state transitions. Simulation experiments are conducted using the benchmark problems of the 3D LWR transient cores provided by NEACRP. The results demonstrate that the DMD-based method effectively predicts the state transitions of core dynamics and xenon transients in nuclear reactors. The accuracy and reliability of the method are validated through the analysis and comparison of predicted results with actual data. Additionally, the impact of model parameters on prediction performance is investigated, and optimization strategies are proposed to further improve the prediction results. The findings of this study offer a novel approach and insights for predicting transient behaviors in the field of nuclear energy. [ABSTRACT FROM AUTHOR]

• A novel MOF-derived MnFeO X electrocatalyst was prepared. • MD-MnFeO X loaded onto the surface of carbon cloth significantly improves the performance of EC/PS system. • The MD-MnFeO X /CC/EC/PMS system has extremely strong environmental stability. • 1O 2 plays a decisive role in the MD-MnFeO X /CC/EC/PMS system. In this work, metal–organic-framework (MOF) derived MnFeO X (MD-MnFeO X) was loaded onto carbon cloth (CC) formed MD-MnFeO X /CC anode. Subsequently, the ability of MD-MnFeO X /CC anode to electrochemically (EC) activate peroxymonosulfate (PMS) for the degradation of persistent organic pollutants was tested by introducing an electric field. The degradation results indicated that the MD-MnFeO X /CC/EC/PMS system had a degradation ability of 90.20 % for tetracycline (TC) within 20 min at a very low current density of 5 mA/cm2, which was significantly higher than that of CC/EC/PMS (53.75 %) and the reported conventional synthesized double transition metal oxide/EC/PMS electrocatalytic system. In addition, the system had excellent stability and low energy consumption (0.79 kWh/m3). The influencing factors of the degradation efficiency of the system were analyzed, and the degradation ability of the system in actual water bodies was tested. The results demonstrated that the system maintained a stable degradation efficiency in various influencing factors and actual water bodies, proving that the system could degrade organic pollutants in complex water bodies. Mechanistic analysis showed that singlet oxygen (1O 2) played a dominant role in the MD-MnFeO X /CC/EC/PMS system. Finally, the pathway for TC degradation in this system was explored. This experiment provides an economically feasible method to improve the electrocatalytic performance of CC electrodes. [ABSTRACT FROM AUTHOR]

[Display omitted] • Porous NiCo 2 O 4 nanosheet array is designed using interfacial engineering. • NiCo 2 O 4 -PMS system oxidizes TC efficiently with practicality. • Good morphological and electronic structure enhances mass and electron transfer. • TC oxidization is dominated by 1O 2 and electron transfer process. The rational design of the morphology and structure of bimetallic-based heterogeneous Fenton-like catalyst derived from metal-organic-frameworks (MOFs) for peroxymonosulfate (PMS) activation via a non-radical pathway is attractive but challenging. Herein, a spinel-type 3D hierarchical porous NiCo 2 O 4 nanosheet array for the activation of PMS is rationally designed by surfactant-assisted interfacial engineering. The experimental results showed that the NiCo 2 O 4 /PMS system demonstrated remarkable oxidative degradation of tetracycline (TC) through 1O 2 attack and electron transfer process. In literature, it was thought that the PMS activation process in above system is dominated by radical pathway. In this work, we employ surfactant modified-nanostructure engineering to design hierarchical mesoporous nanosheet array structures and combined them with intrinsic bimetallic synergy to enhance catalytic activity, and interestingly the strategy transformed the PMS activation pathway into a nonradical (1O 2 and electron transfer)-dominated process. This is benefit from the favorable morphological and electronic structure of the designed catalysts to facilitate mass transfer and electron transfer processes. The system also possessed a broad spectrum for degrading other typical contaminants, and was effective in tolerating actual water matrix and pH changes, as well as resisting interference from anions and organic matter. Furthermore, the robust stability of the structure and catalytic activity make it promising for practical water treatment. It can be expected that this proposal will provide insights for the delicate structural design and the understanding of its PMS activation mechanism of bimetallic-based Fenton-like catalysts, as well as for the efficient degradation of emerging organic pollutants. [ABSTRACT FROM AUTHOR]

The perovskite material has received much attention due to its excellent photoelectric properties. However, the toxicity of Pb has always affected the wide application of perovskite materials. Herein, we proposed to replace Pb ions with the same divalent ions Ba and dope them into the CsPbBr3 perovskite nanocrystals' (PNCs) lattice to reduce the content of Pb elements. In this work, we have successfully prepared a series of CsPb1−xBaxBr3 PNCs (x = 0, 0.1, 0.2, 0.3, and 0.4) and CsPbBr3 PNCs (Ba-doped concentration = x = 0, 0.05, 0.10, 0.15, and 0.20); the best among them were CsPb0.7Ba0.3Br3 PNCs and CsPbBr3 (Ba = 0.1) PNCs, respectively. Compared with CsPbBr3 PNCs, the photoluminescence (PL) intensity of CsPb0.7Ba0.3Br3 PNCs and CsPbBr3 (Ba = 0.1) PNCs has been improved to different degrees. It was worth mentioning that after the addition of a Ba element, the photoluminescent quantum yield (PLQY) of CsPb0.7Ba0.3Br3 PNCs and CsPbBr3 (Ba = 0.1) PNCs was increased to 81% and 65%, respectively. It was due to the high PLQY of CsPb0.7Ba0.3Br3 PNCs that the selected CIE color coordinate monochromatic light encompassed 119.0% of NTSC color gamut. [ABSTRACT FROM AUTHOR]

Photocatalysts based on Z-scheme heterostructure have been extensively investigated for CO 2 reduction and hydrogen production, which solve the problem of high electron-hole pair complexation and low reduction and oxidation capacity in photocatalysts. Here, two-dimensional CuTiO 3 /g-C 3 N 4 (CTO/CN) photocatalysts with directly Z-scheme heterostructure are prepared by effective manipulation of different components of CuTiO 3 (CTO) nanoparticles on 2D (two-dimension) porous g-C 3 N 4 (CN) nanosheets via in-situ growing strategy. Benefited from the special electronic structure, it demonstrates that the 4.0 % CTO/CN sample has an excellent photocatalytic activity for the reduction of CO 2 to H 2 (at a speed of 19.56 μmol g−1 h−1) and CO (at a speed of 19.93 μmol g−1 h−1), which are upper than those of pure g-C 3 N 4 by 43.5 and 17.1 times, respectively. Furthermore, the 4.0 % CTO/CN sample exhibits utstanding performance in electrocatalytic hydrogen production. This synthetic strategy is useful for constructing a 2D Z-scheme heterostructure for applications in energy-related areas. Schematic diagram of electrochemical hydrogen precipitation and carbon dioxide reduction of CuTiO 3 /CN heterojunction composites prepared by in situ growth method. [Display omitted] • A series of CuTiO 3 /g-C 3 N 4 nanosheets were prepared by applying in situ growth method. • CuTiO 3 /g-C 3 N 4 exhibits excellent performance for CO 2 reduction under visible light irradiation. • The 4.0 % CTO/CN had excellent electrochemical stability performance under neutral conditions. [ABSTRACT FROM AUTHOR]

In this work, a series of perovskite nanocrystals glasses with different concentrations of Tb3+ doped CsPbI 3 , which have excellent characteristics in terms of water resistance and cyclic thermal stability, were prepared by melt quenching and in situ crystallization methods. With the introduction of Tb3+, the photoluminescence quantum yield of CsPbI 3 was greatly improved. Considering that the two fluorescence peaks of Tb3+ and CsPbI 3 at different positions respond differently to temperature stimuli, we studied the potential application of those glasses as optical temperature detection tools in the temperature range of 80−480 K. More importantly, the results showed higher sensitivity than other tools, with the maximum absolute and relative temperature sensitivities reaching as high as 0.034 K−1 and 1.78 % K-1, respectively. This work is expected to provide an effective method for the application of CsPbX 3 in high-performance optical temperature sensing materials. [ABSTRACT FROM AUTHOR]

• 2D/0D g-C 3 N 4 /CdS-nitrogen doped hollow carbon spheres (NHCs) hybrids were prepared. • Electronic properties were calculated based on density functional theory. • The g-C 3 N 4 /CdS-NHCs exhibited high visible-light-photodegradation for cloxacillin. • The synergy of g-C 3 N 4 /CdS and NHCs endowed the improved photocatalytic activity. • Active substances h+, O 2 −, and OH worked together in the photocatalytic process. Herein, the high surface area and efficient visible light (VSL) induced photocatalyst, namely 2D/0D g-C 3 N 4 /CdS-nitrogen doped hollow carbon spheres (NHCs) composites have been prepared. Firstly, the physicochemical, photoelectric and electronic structures (including band structure, density of state and charge density difference) properties of the obtained samples were studied. Then, the photocatalytic experiments indicated that the g-C 3 N 4 /CdS-NHCs composites performed a markedly improved VSL photocatalytic performance and photostability for cloxacillin antibiotic degradation compared with pure g-C 3 N 4 , CdS and g-C 3 N 4 /CdS heterojunction. The enhanced photocatalytic performance of g-C 3 N 4 /CdS-NHCs composites could ascribe to the synergy between g-C 3 N 4 /CdS heterojunction and NHCs, which obviously improved the specific surface area, the absorption of VSL, the transfer rate of electrons and the separation efficiency of photogenerated electron-hole pairs of the photocatalysts. Finally, the mechanism analysis showed that active substances h+, O 2 −, and OH worked together in the photocatalytic process, which attack the β-lactam, thiazolidine ring and amide group should be the fatal act for CLX mineralization. [ABSTRACT FROM AUTHOR]

Abstract Particles with a diameter of <2.5 μm (PM 2.5) have serious adverse-effects on human health, which have caused widespread public concern in recent decades. Currently, most of the existing research on PM 2.5 have used linear regression analysis; very few studies on the subject have been conducted using non-linear models. This study adopts a panel threshold model, which is seldom used in environmental studies, to examine the non-linear effects of environmental regulation and economic growth on PM 2.5 in 30 OECD countries, and we also explore the key driving socio-economic factors for PM 2.5 emissions. The results of our analysis show that, along with an increase in environmental policy stringency, PM 2.5 emissions first rise and then show no significant correlations, and thus a reduction in emissions can be expected if current trends continue. As for GDP per capita, significant and negative correlations are found across the three phases divided by the panel threshold model, indicating a promoting effect for PM 2.5 mitigation. In addition, public expenditure on the air sector correlated positively with PM 2.5 concentrations, expanding the share of service economy reward to reduce air pollution, and urban population ratio exhibits an inverted U-shaped pattern. Future studies may shed more light on the regulation-PM 2.5 nexus, and more studies are needed to confirm the existence of bi-directional correlations between economic development and air pollution. Graphical abstract Unlabelled Image Highlights • Environmental regulation show different impacts on PM 2.5 at high-, mid- and low-level phases; • GDP per capita is negatively correlated with PM 2.5 at 1% level; • Expansion of service industry reduces pollution; • An inverted U-shaped relationship exist between urbanization and pollution. [ABSTRACT FROM AUTHOR]

A high-performance piezoelectric photocatalyst (V-BiOIO 3 /FTCN) was constructed to improve removal efficiency of tetracycline hydrochloride (TCH). The role of V-BiOIO 3 in the composite was to introduce piezoelectric effect and construct S-scheme heterojunction photocatalyst with fish scale tubular carbon nitride (FTCN). The morphology, structure, chemical composition and optoelectronic characteristics of the as-prepared photocatalysts were studied by SEM, TEM, XRD, XPS and UV-Vis DRS. Combined with UV-Vis DRS, XPS valence band, Mott-schottky curve and theoretical calculations, the mechanism of TCH degradation was deeply analyzed. A series of degradation experiments showed that the V-BiOIO 3 /FTCN could effectively degrade TCH, and the removal efficiency was further improved under the action of ultrasound. Importantly, the further immobilized V-BiOIO 3 /FTCN/MS could float on the water surface to degrade TCH without additional stirring, which facilitated the recovery of photocatalysts and showed excellent practical application value. This work provided a reference for the design and immobilization of carbon nitride-based piezoelectric photocatalysts. [Display omitted] • Novel piezoelectric photocatalyst V-BiOIO 3 /FTCN was successfully prepared. • The transfer style of e and h+ between V-BiOIO 3 and FTCN belonged to S-scheme. • The mechanism was explored through experiments and theoretical calculations. • The floatable V-BiOIO 3 /FTCN/MS had good practical application prospects. [ABSTRACT FROM AUTHOR]

[Display omitted] • Supramolecular self-assembly produced tubular g-C 3 N 4 precursors. • H 2 O 2 impregnated precursors achieve the multi-mesoporous filling in tubular g-C 3 N 4. • Endogenous gas release promoted the formation of porous structures. • Investigating the physicochemical properties by experiment and DFT calculation. The problem that the hollow part with macroporous size in the hollow tubular g-C 3 N 4 is difficult to function in photochemical reactions has been neglected for a long time. To address this issue, tubular g-C 3 N 4 with mesoporous-rich non-hollow ant nest-like filling (AN-TCN) was prepared by calcining supramolecular precursors impregnated with hydrogen peroxide solution. The endogenous gas released from the wet rod-like supramolecular precursor during thermal polymerization contributed to the construction of a mesoporous filling structure inside the AN-TCN, which not only increased the reactive sites, but also enhanced the ability of visible light response and facilitated the separation and transfer of photoinduced charges. Experiments and theoretical calculations were conduct together to reveal the physicochemical characteristics of AN-TCN. The photocatalytic capacity of AN-TCN-4.5 for tetracycline hydrochloride (TCH) reached to 86 % under visible radiation within 30 min. This study afforded a new thinking and strategy for morphology regulation and performance optimization of g-C 3 N 4 -based photocatalyst. [ABSTRACT FROM AUTHOR]

[Display omitted] • The PLQY of CsPbBr 3 /Cs 4 PbBr 6 @PDMS achieve to 71%. • CsPbBr 3 /Cs 4 PbBr 6 @PDMS composite was studied for the first time and exhibit excellent optical properties. • The stabilit ies of CsPbBr 3 against heat, water and UV light have been greatly improved. • Under the excitation of blue chip, the color coordinate is extremely close to the standard of white light color coordinate. • The as-prepared film with the color gamut that could reach to 127% of NTSC 1953 and 95% of Rec. 2020 and applied in LCD successfully. All-inorganic perovskites have been considered next-generation color converters in the backlit due to their shining optical properties. However, structural instability severely limits their pragmatic applications. Here, CsPbBr 3 /Cs 4 PbBr 6 microcrystals (MCs) were successfully embedded in polydimethylsiloxane (PDMS) films by a facile two-step method. As-prepared PDMS films containing CsPbBr 3 /Cs 4 PbBr 6 MCs (CsPbBr 3 /Cs 4 PbBr 6 @PDMS) obtain high brightness and excellent stability. Meaningfully, the PDMS films not only serve as a double protective matrix that can be used to improve the stability of CsPbBr 3 /Cs 4 PbBr 6 MCs, but also a flexible substrate with high transparency that allows the CsPbBr 3 /Cs 4 PbBr 6 @PDMS films to be used as color conversion materials for backlit displays. To our surprise, when PDMS is coated with CsPbBr 3 /Cs 4 PbBr 6 MCs, the water, thermal and photostability are greatly improved, while the photoluminescence intensity only lost by 10%. Furthermore, by mixing CsPbBr 3 /Cs 4 PbBr 6 MCs with K 2 SiF 6 :Mn4+ phosphors in PDMS, a monolithic film with high performance was obtained. Its color gamut can reach 127% of the NTSC 1953 standard and 95% of the REC. 2020 standard, exhibiting the bright prospects in the backlit display field. [ABSTRACT FROM AUTHOR]

Removal of harmful organic matters from environment has great environmental significance. Carbon nanotube (CNT) materials and their composites have been demonstrated to possess excellent catalytic activity towards persulfate (PS) activation for the degradation of organic contaminants. Herein, detailed information concerning the function, modification methods and relevant mechanisms of CNT in persulfate-based advanced oxidation processes (PS-AOPs) for organic pollutant elimination has been reviewed. The activation mechanism of PS by CNT might include radical and nonradical pathways and their synergistic effects. The common strategies to improve the stability and catalytic capability of CNT-based materials have also been put forward. Furthermore, their practical application potential compared with other catalysts has been described. Finally, the challenges faced by CNT in practical application are clearly highlighted. This review should be of value in promoting the research of PS activation by CNT-based materials for degradation of organic pollutants and the corresponding practical applications. [Display omitted] • Application of CNT based composites presents great potential in PS activation. • OFGs, defects and high conductivity are conducive to activation. • Both radical and nonradical pathways are responsible for the activation. • Crossover technologies might be future research direction. [ABSTRACT FROM AUTHOR]

In the face of the increasingly serious water pollution problem, sulfate radical-based advanced oxidation processes gradually developed due to their remarkable ability to degrade refractory organic pollutants. Spinel ferrite nanoparticles (NPs) and their nanocomposites (NCs) can be used as catalysts to activate peroxymonosulfate (PMS) with great catalytic performance, high stability, and reusability, which has attracted some attention of scholars in recent years. Firstly, the advantages and mechanisms of PMS activation induced by various spinel ferrite NPs and their NCs for organic pollutants removal are reviewed in this paper. Secondly, the influence factors of catalyst performance and PMS activation are discussed. Finally, the challenges of PMS activation induced by spinel ferrite NPs and their NCs are put forward and the direction of improvement is proposed. [Display omitted] • Recent advances of spinel ferrite NPs and their NCs in peroxymonosulfate activation are reviewed. • The frequently-used synthesis methods, activation mechanisms, and influence factors are discussed. • Challenges and the direction of improvement are provided. [ABSTRACT FROM AUTHOR]

The photo-Fenton-like catalytic process has shown great application potential in environmental remediation. Herein, a novel photo-Fenton-like catalyst of Bi 2 WO 6 nanosheets decorated hortensia-like CoAl-layered double hydroxides (Bi 2 WO 6 /CoAl-LDHs) was synthesized via hydrothermal process. The optimized Bi 2 WO 6 /CoAl-LDHs composite performed the high-efficiency photo-Fenton-like catalytic performance for oxytetracycline (OTC) removal (98.47%) in the mediation of visible-light and H 2 O 2. The comparative experiment, technical characterization and density functional theory calculation results indicated that the efficient photo-Fenton-like catalytic performance of Bi 2 WO 6 /CoAl-LDHs was attributed to the synergistic action of the Fenton-like process of cobalt ions in CoAl-LDHs, an internal electric field and the S-scheme heterojunction form between Bi 2 WO 6 and CoAl-LDHs, which could significantly promote the active substance formation and the photocatalytic process in the catalytic system. This study will stimulate the new inspiration of designing the efficient catalytic system for environmental remediation and other fields. [Display omitted] • Hortensia-like Bi 2 WO 6 /CoAl-LDHs composite was synthesized via hydrothermal process. • Optical-electrical properties and H 2 O 2 adsorption behavior of samples were calculated by DFT. • Bi 2 WO 6 /CoAl-LDHs composite exhibited high photo-Fenton-like catalytic activity of antibiotic. • An internal electric field and S-scheme heterojunction form between Bi 2 WO 6 and CoAl-LDHs. [ABSTRACT FROM AUTHOR]

Due to the low efficiency of single-component nano materials, there are more and more studies on high-efficiency composites. As zero dimensional (0D) non-metallic semiconductor material, the emergence of graphene quantum dots (GQDs) overcomes the shortcomings of traditional photocatalysts (rapid rate of electron-hole recombination and narrow range of optical response). Their uniqueness is that they can combine the advantages of quantum dots (rich functional groups at edge) and sp2 carbon materials (large specific surface area). The inherent inert carbon stabilizes chemical and physical properties, and brings new breakthroughs to the development of benchmark photocatalysts. The photocatalytic efficiency of GQDs composite with semiconductor materials (SCs) can be improved by the following three points: (1) accelerating charge transfer, (2) extending light absorption range, (3) increasing active sites. The methods of preparation (bottom-up and top-down), types of heterojunctions, mechanisms of photocatalysis, and applications of GQDs/SCs (wastewater treatment, energy storage, gas sensing, UV detection, antibiosis and biomedicine) are comprehensively discussed. And it is hoped that this review can provide some guidance for the future research on of GQDs/SCs on photocatalysis. [Display omitted] • The synthesis methods of GQDs/SCs are summarized. • The roles of GQDs in improving the photocatalytic efficiency of SCs are emphasized. • Photoelectric properties and biocompatibility make GQDs/SCs are used in environment, biomedicine, etc. • The opportunities and challenges of GQDs/SCs are described. [ABSTRACT FROM AUTHOR]

Recently, persulfate-based advanced oxidation processes (persulfate-AOPs) are booming rapidly due to their promising potential in treating refractory contaminants. As a type of popular two-dimensional material, layered double hydroxides (LDHs) are widely used in energy conversion, medicine, environment remediation and other fields for the advantages of high specific surface area (SSA), good tunability, biocompatibility and facile fabrication. These excellent physicochemical characteristics may enable LDH-based materials to be promising catalysts in persulfate-AOPs. In this work, we make a summary of LDHs and their composites in persulfate-AOPs from different aspects. Firstly, we introduce different structure and important properties of LDH-based materials briefly. Secondly, various LDH-based materials are classified according to the type of foreign materials (metal or carbonaceous materials, mainly). Latterly, we discuss the mechanisms of persulfate activation (including radical pathway and nonradical pathway) by these catalysts in detail, which involve (i) bimetallic synergism for radical generation, (ii) the role of carbonaceous materials in radical generation, (iii) singlet oxygen (1O 2) production and several special nonradical mechanisms. In addition, the catalytic performance of LDH-based catalysts for contaminants are also summarized. Finally, challenges and future prospects of LDH-based composites in environmental remediation are proposed. We expect this review could bring new insights for the development of LDH-based catalyst and exploration of reaction mechanism. [Display omitted] • Systematic introduction of different persulfate activation mechanisms by LDH-based catalysts. • Unique "intercalation effect" of LDH-based catalysts have been discussed. • Discussion on the effect of tailoring the morphology of LDHs for improving catalytic performance. [ABSTRACT FROM AUTHOR]

[Display omitted] • Bifunctional KHCO 3 template-mediated synthesis of porous and well-structured g-C 3 N 4. • Cyano defects and K intercalation are introduced into g-C 3 N 4 framework. • Catalysts owns tunable band structure, optimized charge transfer. • The mechanism is well studied by experiments and theoretical calculations. • The photocatalyst exhibits an excellent ability to produce H 2 O 2 under visible light. The photocatalytic method to produce hydrogen peroxide (H 2 O 2) as a substitute for fossil fuels has become a hot research topic. We herein propose cyano defect and potassium intercalation modified g-C 3 N 4 photocatalysts in which the porous structure and crystallinity can be maintained relatively well. Simultaneously, the photocatalysts possess adjustable band structure, enhanced carrier transfer efficiency and highly selective dual-electron O 2 reduction. The physicochemical properties and reaction mechanisms are well studied through the effective combination of experiments and theoretical calculations. The H 2 O 2 yield of KDCN-0.2 (278.9 μmol L-1h−1) is approximately 4.3 times higher than that of original CN (65.2 μmol L-1h−1), and the energy conversion efficiency is also higher than many current CN-based photocatalysts. This work deepens the understanding of the mechanism of photocatalytic O 2 reduction for H 2 O 2 production and points out the promising direction for the design of novel CN-based photocatalysts with ideal properties in energy conversion and environmental applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • Novel fish-scale tubular carbon nitride (FTCN so) was successfully prepared. • FTCN so has abundant structural defects and excellent photocatalytic performance. • The role of trithiocyanuric acid is used to build the skeleton, not for S doping. • The new 1D tubular carbon nitride composite material (Znln 2 S 4 /FTCN so) was constructed. • Znln 2 S 4 /FTCN so has excellent photocatalytic degradation tetracycline and production H 2 O 2 performance. A fish-scale tubular carbon nitride (FTCN so) and its heterojunction ZnIn 2 S 4 /FTCN so were constructed to enhance the ability of photocatalytic tetracycline degradation and H 2 O 2 production under visible light. The photocatalysts were analyzed through a variety of techniques. Firstly, the surface of FTCN so was composed of fish-scale nanoplatelets with abundant structural defects by SEM. Secondly, the results of UV–vis and theoretical calculation proved the improvement of visible light absorption performance of ZnIn 2 S 4 /FTCN so. Thirdly, the electrochemical tests confirmed the ZnIn 2 S 4 /FTCN so effectively inhibited the recombination of photogenerated e−-h+ pairs. Meanwhile, the electronic-structural properties and photocatalytic mechanism were systematically and deeply studied by combining UV–vis, XPS valence band, theoretical calculations and capture experiments of active species in different pH solution. ZnIn 2 S 4 /FTCN so exhibited excellent performance in photocatalytic tetracycline degradation and H 2 O 2 production under visible light due to the special structure and the existence of heterojunction. This work provides guidance for the development and design of new multifunctional carbon nitride-based materials. [ABSTRACT FROM AUTHOR]

[Display omitted] • Sulfur doped hollow tubular g-C 3 N 4 was prepared through molecular self-assembly. • A noval 2D/1D BOC/SCN hierarchical heterostructure was constructed. • BOC/SCN composites exhibited outstanding photocatalytic activity and stability for TCH degradation. • A possible Z-scheme charge transfer pathway and degradation mechanism were proposed. The construction of heterojunction photocatalysts was considered to be an effective strategy to tackle refractory pollutants. However, most of the reported composites lacked precise control of their morphology, resulting in unsatisfactory catalytic activity. In this work, we successfully fabricated sulfur doped g-C 3 N 4 hollow tubes (SCN) via molecular self-assembly, and then grew the Bi 2 O 2 CO 3 nanoflakes (BOC) in situ parallel on the surface of SCN to construct 2D/1D interfacial phase. Within 30 min visible light irradiation, the robust BOC/SCN-3 heterostructure showed considerable improvement for tetracycline degradation (82.6%) compared with individual components. This enhanced photocatalytic performance derived from the synergistic effect of S doping and heterojunction interface contact. The tubular structure formed by S doping not only narrowed the bandgap and thus boosting the visible light harvesting of CN, but also promoted electrons to travel along the 1D longitudinal and radial directions. In addition, the built-in electric field between BOC and SCN effectively achieved the spatial separation of electron-hole pairs. Mechanism analysis revealed that the h+ and •O 2 − radicals played the dominating contribution in the photocatalytic process, and a possible Z-scheme mechanism was proposed. It was expected that such design route could provide a new perspective on hierarchical heterostructure for pollutant removal. [ABSTRACT FROM AUTHOR]

[Display omitted] • The magnetic covalent organic frameworks (MCOFs) are divided into three categories. • The main characteristics of MCOFs and different synthesis methods are introduced. • The application scope of MCOFs is comprehensively investigated. • The application mechanism of MCOFs in various aspects is explained reasonably. • The future development and challenges of MCOFs have been prospected. Magnetic nanoparticles (MNPs) possess outstanding rapid magnetic separation ability due to their excellent superparamagnetism and stability. Covalent organic frameworks (COFs) have the advantages of porous structure, large specific surface area, remarkable acid–base and thermal stability that can form novel magnetic nanocomposites with MNPs. The formed magnetic covalent organic frameworks (MCOFs) composite material owns high saturation magnetization and prominent chemical stability, which is the great potential material in the fields of environmental remediation and biological applications. Based on the current research results, firstly, this review further simplifies the classification according to the composition and functionalization of the composite: primitive MCOFs, functionalized MCOFs, composite of Fe/Co/Ni and its alloys with COFs. Secondly, several major characteristics and diverse synthesis methods of MCOFs composites are described. Thirdly, the applications of MCOFs in adsorption and enrichment detection, catalysis, sensing and biomedical aspect are reviewed in detail, and the mechanisms of these processes have been fully and reasonably explained. Finally, the future development and challenges of MCOFs composite materials have been prospected. This work aims to provide a theoretical basis for the synthesis and design of MCOFs composite materials in the future. [ABSTRACT FROM AUTHOR]

[Display omitted] Sulfate radical-based advanced oxidation processes (SR-AOPs) have received intensively attention due to the ability and adaptability. Biochar-based catalysts have been regarded as the effective catalysts for activating peroxymonosulfate (PMS) to generate sulfate radicals (SO 4 •-). This article discussed the advance of the PMS activation by biochar-based catalysts. Firstly, the sources and synthesis methods of biochar-based catalysts have been discussed. Secondly, the different activation mechanisms (including radical pathways and non-radical pathways) of pristine biochar, heteroatom doping biochar and biochar composites catalysts for PMS activation are reviewed, respectively, which includes (i) the significant role of persistent radical (PFRs) and the special structures (defects and graphitization) of pristine biochar, (ii) the effects of element doping (especially N atom) and metal species on the biochar catalysts, (iii) the production mechanisms of reactive oxygen species (ROS) and special non-radical mechanism. Thirdly, the influences of PMS and catalysts concentration, temperature, pH, anions and natural organic matter (NOM) on the contaminants degradation process have been presented. Finally, the conclusion and prospects section discussed the challenges and possible future directions for the degradation of contaminants by biochar/PMS systems. This review is expected to provide new ideas for the application of biochar-based catalysts and broaden the ways for the removal of organic contaminants. [ABSTRACT FROM AUTHOR]

• Ultrathin, porous and vacancy-rich CoAl-LDHs nanosheets were prepared by exfoliation strategy. • 2D/2D CoAl-LDHs/Ti 3 C 2 T x hybrids were synthesized via electrostatic assembly process. • Electronic and optical properties were calculated based on density functional theory. • CoAl-LDHs/Ti 3 C 2 T x hybrids exhibited high visible-light photodegradation of antibiotic. • Synergistic effect between CoAl-LDHs and Ti 3 C 2 T x endowed the excellent photocatalytic activity. The layered double hydroxides (LDHs) are potential non-noble metal photocatalysts. Unfortunately, the intrinsic activity of bulk LDHs is relatively low, which limits their use. Herein, the ultrathin, porous and vacancy-rich CoAl-LDHs nanosheets were prepared by exfoliation strategy. Then, they were assembled with the early transition-metal carbides nanosheets (MXenes, Ti 3 C 2 T x) to afford a hybrid 2D/2D CoAl-LDHs/Ti 3 C 2 T x photocatalyst via electrostatic assembly process. The experiments indicated that the CoAl-LDHs/Ti 3 C 2 T x hybrids performed an excellent visible-light photocatalytic activity for tetracycline hydrochloride (96.67 %) degradation. Diversified characterization techniques (SEM, TEM, AFM, N 2 adsorption-desorption analysis, XRD, FTIR, UV–vis DRS, photoelectrochemical test) and density functional theory calculations (electronic and optical properties) have indicated that such excellent photocatalytic activity was ascribed to the synergy and the Schottky heterojunction formation between CoAl-LDHs nanosheets and Ti 3 C 2 T x nanosheets, which possessed markedly visible-light absorption, high specific surface area, rapid electrons transfer and depressed electron-hole pairs recombination. [ABSTRACT FROM AUTHOR]

Energy shortages and climate change call for the development of clean and sustainable energy. The development of green materials for clean energy storage and conversion is conducive to promoting the widespread use of clean energy. Conjugated microporous polymers (CMPs) have been synthesized with various structures and properties, which offer designability for the molecular structures and nanopores of conjugated skeletons. The research of CMPs in clean energy technologies is significant for the improvement of CMP-based materials and their application in energy and environmental engineering. CMPs have shown great potential for challenging energy and environmental issues such as gas adsorption, photocatalysis, solar energy conversion, and electrical energy storage and conversion. This review aims to summarize the advances of synthesis and design on CMPs, computer simulations on CMPs, and the applications of CMPs in the clean energy technologies including hydrogen evolution and storage, the adsorption and conversion of carbon dioxide, rechargeable batteries, supercapacitors, fuel cells, and photovoltaic cells. We also propose the challenges and potential chances of the synthesis and the clean energy applications of CMPs. [Display omitted] [ABSTRACT FROM AUTHOR]

• Melamine self-assembly can adjust the shape and structure of the material. • Melamine self-assembly is an effective measure to synthesize high-performance g-C 3 N 4 -based materials. • The type, mechanism, influencing factors and recent advances of self-assembly are highlighted. • Provides guidance for scientific researchers to develop and design high-performance g-C 3 N 4 -based materials. The increasing pollution of the environment and the depletion of energy are currently facing and urgently need to be resolved. In recent years, various technologies have been exploited to try to solve these problems. Researchers are mainly committed to developing high-performance materials. This review discusses the construction of ordered graphitic carbon nitride (g-C 3 N 4)-based materials by melamine self-assembly. Firstly, the self-assembly types, corresponding synthesis strategies, characteristics and recent advances are reviewed from the perspectives of material source and product shape. Meanwhile, the effects of molecular structure, solution environment, synthesis methods and the presence of other substances on the self-assembly behavior are also discussed. In addition, we present the synthesis mechanisms from multiple sides. Finally, the applications in environment and energy are summarized, and the future research directions are also proposed. This review provides new insights into the design and construction of high-performance ordered g-C 3 N 4 -based materials for environment and energy. [ABSTRACT FROM AUTHOR]