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An interfacial C-S bond bridged ZnS/C 3 N 5 S-scheme heterojunction was constructed for photocatalytic H 2 evolution. Benefiting from the interfacial covalent bond, enhanced internal-electric-field strength, and accelerated surface photocatalytic reaction, the photocatalytic H 2 production of ZnS/C 3 N 5 was 3.2 and 2.5 times higher than those of ZnS/C 3 N 4 and ZnS/C 3 N 5 -300 without C-S bond. [Display omitted] • C-S bond is susceptive to preparation temperatures, and it is broken above 300 °C. • C-S bond promotes e − separation and improves H 2 O adsorption and activation behaviors. • IEF strength of ZnS/C 3 N 5 with opposite direction is 2.6 times than that of ZnS/C 3 N 4. • e − transfer respectively follow S-scheme and type-II pathway in ZnS/C 3 N 5 and ZnS/C 3 N 4. • H 2 yield of ZnS/C 3 N 5 is 3.2 and 2.5 times than ZnS/C 3 N 4 and ZnS/C 3 N 5 -300 without C-S. An interfacial C-S bond bridged ZnS/C 3 N 5 heterojunction was constructed for photocatalytic H 2 evolution. Different from traditional type-II ZnS/C 3 N 4 heterojunction, the electron transfer followed S-scheme pathway, due to opposite internal-electric-field (IEF) directions in these two heterojunctions. The C-S bond formation was carefully investigated, and they were susceptive to the preparation temperatures. In photocatalytic reaction, C-S bond was functioned as the "high-speed channel" for electron separation and transfer, and the IEF strength in ZnS/C 3 N 5 was 1.86 × 108 V/m, 2.6 times higher than that in ZnS/C 3 N 4. Moreover, the C-S bond also altered the surface molecular structure of ZnS/C 3 N 5 , and hence the surface reaction was accelerated via improving H 2 O adsorption and activation behaviors. Benefiting from the S-scheme pathway, enhanced IEF strength, and accelerated surface reaction, the photocatalytic H 2 production over ZnS/C 3 N 5 reached up to 20.18 mmol/g/h, 3.2 and 2.5 times higher than those of ZnS/C 3 N 4 and ZnS/C 3 N 5 -300 without C-S bond. [ABSTRACT FROM AUTHOR]

[Display omitted] • NH 4 BS can dissolve in basic electrolyte without cosolvent. • NH 4 BS can alleviate the passivation of electrode surfaces by dissolving Li 2. • NH 4 BS can increase the dissociation degree of long-chain polysulfides.NH4BS can increase the dissociation degree of long-chain polysulfides. Based on the dissolution and conversion mechanism of lithium-sulfur (Li-S) batteries, insulating solid short-chain polysulfides (Li 2 S 2 /Li 2 S) will continuously passivate and corrode the active interface of cathode and anode, which seriously affects its performance. Herein, ammonium benzenesulfonate (NH 4 BS) is proposed as a soluble ammonium salt to dissolve Li 2 S in the ether electrolyte, according to the inductive effect of NH 4 + cation and O atom on Li-S bond. This is beneficial to alleviate the interface problem of electrodes and irreversible loss of active materials. Noticeably, soluble Li 2 S regulates its deposition behavior from 2D to 3D, which is conducive to the more effective use of conductive surface. Moreover, the addition of NH 4 BS can increase the dissociation degree of long-chain polysulfides, so that the diffusion rate and reaction kinetics of active substances are improved. Profiting from these functions, the Li-S cells with NH 4 BS act out excellent cyclic stability in the long cycle of 0.5 C and 2 C. Under the extreme conditions of high sulfur loading and low electrolyte-sulfur ratio, the cells with NH 4 BS can cycle stably for 196 cycles, which significantly prolongs the battery life. The proposal of NH 4 BS broadens a new idea to solve the interface problem of Li-S cells and stimulate the research enthusiasm of developing soluble ammonium salt. [ABSTRACT FROM AUTHOR]

Aboveground biomass (AGB) in grasslands directly reflects the net primary productivity, making it a sensitive indicator of grassland resource quality and ecological degradation. Accurately estimating AGB over large regions to reveal long-term AGB evolution trends remains a formidable challenge. In this study, we divided Inner Mongolia Autonomous Region (IMAR) grasslands into three study regions based on their spatial distribution of grassland types. We combined remote sensing data with ground-based sample data collected over the past 19 years from 6114 field plots using the Google Earth Engine platform. We constructed random forest (RF) and traditional regression AGB inversion models for each region and selected the best-performing model through accuracy assessment to estimate IMAR grassland AGB for the period 2000–2022. We also examined the trends in AGB changes and identified the driving forces affecting IMAR grasslands through the application of Theil-Sen estimation, Mann-Kendall trend analysis, and the Geodetector model. The main findings are as follows: (1) Compared with the univariate parametric traditional regression model, the AGB monitoring accuracy of the multivariate non-parametric RF model in the three study regions increased by 5.94%, 5.08% and 19.14%, respectively. (2) The average AGB per unit area of IMAR grasslands from 2000 to 2022 was 731.41 kg/hm2, with alpine meadow having the highest average AGB (1271.70 kg/hm2) and temperate grassland desertification having the lowest (469.06 kg/hm2). IMAR grasslands exhibited an overall increasing trend in AGB over the past 23 years (6.01 kg/hm2•yr), with the increasing trend covering 83.52% of the grassland area and the decreasing trend covering 16.48%. (3) Spatially, IMAR grassland AGB showed a gradual decline from northeast to southwest and exhibited an increasing trend with increasing longitude (45.423 kg/hm2 per degree) and latitude (71.9 kg/hm2 per degree). (4) Meteorological factors were the most significant factors affecting IMAR grassland AGB, with precipitation (five-year average q value of 0.61) being the most prominent. In the western part of IMAR, where precipitation is consistently limited throughout the year, the primary drivers of influence were human activities, with particular emphasis on the number of livestock (with a five-year average q value of 0.44). It is evident that reducing human activity disturbance and pressure in fragile grassland areas or implementing near-natural restoration measures will be beneficial for the sustainable development of grassland ecosystems. The results of this research hold substantial reference importance for the protection and restoration of grasslands, the supervision and administration of grassland resources, as well as the development of policies related to grassland management. [Display omitted] • The aboveground biomass (AGB) of grasslands in IMAR increased over the past 23 years. • IMAR grassland AGB shows an upward trend with increasing longitude and latitude. • Precipitation is the main factor affecting grassland AGB in IMAR. • Human activities have a greater impact on the grassland AGB in western IMAR. [ABSTRACT FROM AUTHOR]

A hybrid material of N -doped graphitic carbon shell-encapsulated FeCo alloy derived from metal–polyphenol network and melamine sponge is an effective electrocatalyst for ORR, OER, and HER. Exploiting low cost and durable electrocatalysts with high efficiency for oxygen reduction reaction (ORR), oxygen evolution reaction (OER), and hydrogen evolution reaction (HER) is of great significance for energy conversion and storage applications. Herein, a hybrid electrocatalyst of FeCo alloy nanoparticles embedded in a porous N -doped carbon was prepared via a pyrolysis process of low-cost melamine sponge and mass-produced metal–polyphenol network. Benefting from the metal coordination of metal–polyphenol network and abundant N source of melamine sponge, the metal–N moiety and FeCo alloy nanoparticles (wtih a diameter around 50 nm) encapsulated in a N -doped graphene-like carbon layer were formed in-situ. Such intimate integration of graphene-like carbon-encapsulated FeCo alloys, metal–N active species, and porous structure is conducive to improve the catalytic activity and increase the catalytic durability in alkaline media. As a consequence, the as-prepared electrocatalyst exhibits the pronounced activity toward ORR, OER, and HER simultaneously under alkaline condition, particularly on the performances of potential, stability, and methanol tolerance. [ABSTRACT FROM AUTHOR]

• Clusters that are well approximated as tetrairidium were synthesized from Ir(C 2 H 4) 2 complexes anchored to the Zr 6 O 8 nodes of the metal organic framework UiO-67. • The supported clusters catalyze ethylene conversion at 298 K and atmospheric pressure, with the turnover frequency (per Ir atom) characterizing the clusters being twice that of the mononuclear iridium complexes. • The clusters are active exclusively for hydrogenation whereas the mononuclear iridium complexes are active for both dimerization and hydrogenation. • DFT calculations of the reaction energetics are in good accord with experiment, showing that the rate-determining step for the hydrogenation on the isolated iridium complexes is the H 2 activation on iridium, whereas the hydrogenation of an iridium-bound ethyl ligand is rate determining for the cluster. Clusters that are well approximated as tetrairidium were synthesized from Ir(C 2 H 4) 2 complexes anchored to the Zr 6 O 8 nodes of the metal organic framework (MOF) UiO-67 by treatment in H 2 at 353 K. The conversion taking place within the porous MOF structure was monitored by infrared and X-ray absorption spectroscopies, which provide evidence of tetrairidium clusters formed from the mononuclear precursors. The supported clusters were tested in a flow reactor as catalysts for ethylene conversion at 298 K and atmospheric pressure with a 1:1 M feed ratio of H 2 to ethylene. The results show that the turnover frequency (per Ir atom) characterizing the clusters is twice that of the mononuclear iridium complexes, with both catalysts being active for hydrogenation and dimerization and the clusters being less selective than the complexes for dimerization. Density functional theory calculations of the reaction energetics are in good accord with experiment, showing that the rate-determining step for the hydrogenation on the isolated iridium complexes is the H 2 activation on iridium, whereas the hydrogenation of an iridium-bound ethyl ligand is rate determining for the cluster. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • The MoP/CN samples exhibit superior activity in CO 2 reduction and H 2 evolution. • The CO 2 adsorption and conversion progress is well revealed in the photoreaction. • The efficient co-catalyst MoP facilitates the separation and transfer of charges. Abstract Photoreduction CO 2 to hydrocarbons and photosplitting water for H 2 production are the most promising, sustainable approaches for environmental pollution alleviation and solar-to-chemical energy conversion. However, developing low-cost, high efficient and stable photocatalysts remains a great challenge. Herein, we reported a novel visible-light activated MoP co-catalyst loaded g-C 3 N 4 photocatalyst for CO 2 reduction and water splitting under simulated irradiation firstly. Experimental results demonstrated that the composites were highly active and exhibited superior stability. The maximum CO and H 2 evolution rates of 0.92 μmol h−1 and 40.38 μmol h−1 were achieved on MoP/CN-15% catalyst, which were 4.5-fold and 74.5-fold higher than the pure g-C 3 N 4 , and the corresponding apparent quantum efficiencies (AQE) were 3.5% and 18.3% at 420 nm, respectively. In situ FTIR analysis disclosed the CO 2 adsorption and conversion progress, in which the COO− acted as a major intermediate. Furthermore, comprehensive characterization analysis revealed the introduction of MoP facilitated the separation and transfer of photogenerated electron-hole pairs, and the theoretical calculation by density functional theory (DFT) also confirmed that MoP could effectively separate the photoexcited charges from g-C 3 N 4. Combining with experimental and DFT calculations results, a new way to design cost-effective photocatalysts has been enlightened. [ABSTRACT FROM AUTHOR]

Graphene quantum dots (GQDs) have been synthesized reproducibly by chemical oxidation (CO) of carbon nano-onions (nCNOs) and a one-step pulsed laser ablation (LA) of nCNOs in deionized water. The photoluminescence (PL) spectra show that the LA-GQDs have blue shifted emission relative to the CO-GQDs which is attributed to the effects of both particle sizes and surface functional groups. The CO-GQDs have an average diameter of 4.1(8) nm and a thickness corresponding to two or three graphene layers, while the LA-GQDs have an average diameter of 1.8(6) nm and a thickness comparable to a single layer of graphene. The CO-GQDs favor the presence of carboxylic groups and have a higher fraction of sp 2 carbons, while the LA-GQDs prefer the presence of hydroxyl groups and have a higher fraction of sp 3 carbons. PL lifetime data suggests that surface functional groups are the main source of radiative deactivation and the sp 2 carbon domains are mainly responsible for non-radiative decay. PL lifetimes are measured to be 7.9(6) ns for the emission from the carboxylic groups and 3.18(10) ns from the hydroxyl groups. Compared to CO, liquid-phase LA is a faster and cleaner one-step method for producing GQDs with fewer starting chemicals and byproducts. [ABSTRACT FROM AUTHOR]

This paper analyzes how to achieve the cost-effectiveness by initial allocation of CO 2 emission permits when a single dominant firm in production market has market power in auction, and compare two prevalent allocation patterns, mixed allocation and single auction. We show how the firm with market power may manipulate the auction price, thereby this leads to fail to achieve cost-effective solution by auction unless the total permits for allocation equal to the effective emissions cap. Provided that the market power firm receives strictly positive free permits, the effective emissions cap of mixed allocation is larger than that of single auction. The production market share of dominant firm is increasing with the free permits it holds. Finally, we examine the compliance costs and welfare of mixed allocation and single auction, the result show that the former is preferred to the later when policy makers consider economic welfare without welfare cost due to CO 2 emissions. [ABSTRACT FROM AUTHOR]

Let R be an isolated Gorenstein singularity with a non-commutative resolution A = End R ( R ⊕ M ) . In this paper, we show that the relative singularity category Δ R ( A ) of A has a number of pleasant properties, such as being Hom-finite. Moreover, it determines the classical singularity category D s g ( R ) of Buchweitz and Orlov as a certain canonical quotient category. If R has finite CM type, which includes for example Kleinian singularities, then we show the much more surprising result that D s g ( R ) determines Δ R ( Aus ( R ) ) , where Aus ( R ) is the corresponding Auslander algebra. The proofs of these results use dg algebras, A ∞ Koszul duality, and the new concept of dg Auslander algebras, which may be of independent interest. [ABSTRACT FROM AUTHOR]

Supported rhodium acetate dimers were prepared by the reaction of Rh 2 (OAc) 4 (OAc is acetate) with highly dehydroxylated MgO powder and characterized by extended X-ray absorption fine structure and infrared (IR) spectra, which show that the supported species were well represented as Rh 2 (OAc) 3 , with each Rh atom on average bonded to one oxygen atom of the MgO surface. Aberration-corrected scanning transmission electron microscopy gave images of Rh atoms in pairs on the MgO. The supported rhodium dimers were probed with a pulse of CO, and the IR spectra indicate a Rh(II) species with weakly bonded carbonyl ligands; the sharpness of the ν CO band indicates highly uniform surface species. Further treatment in CO led to breakup of the rhodium dimers into mononuclear species; such fragmentation took place in other treatment gases as well, with the degree of fragmentation decreasing in the order CO > C 2 H 4 > helium. The fragmentation is inferred on the basis of IR spectra to have proceeded through intermediate Rh 2 species without acetate ligands. In contrast, rhodium dimers were reduced and not fragmented in the presence of H 2 at 353 K, but at higher temperatures the rhodium aggregated to give larger clusters. The supported species catalyzed ethylene hydrogenation at 298 K and 1 bar at a H 2 :ethylene molar ratio of 4; after 27 h of catalysis in a once-through flow reactor, acetate ligands were removed from the dimers, and some of them fragmented, as shown by IR spectroscopy. The intermediate dirhodium species without acetate ligands are two or three orders of magnitude more active as catalysts than the supported mononuclear rhodium species or those present predominantly as Rh 2 (OAc) 3 , respectively. [ABSTRACT FROM AUTHOR]

We consider optimal locations of heat diffusion and related optimal control to achieve null controllability for multi-dimensional heat equations. Both time optimal control and norm optimal control problems are considered. The reason behind combining these two problems together is that these two problems are actually equivalent: The energy to be used to drive the system to zero in minimal time interval is actually the minimal energy of driving the system to zero in this minimal time interval and visa versa. We formulate the optimal locations for time optimal control and norm optimal control into two types of shape optimization problems. One is seeking the optimal domain of heat diffusion with a fixed interior actuator domain. This can be considered as a domain perturbation problem in shape optimization. Another is to seek both the optimal locations of the optimal heat diffusion domain and the related optimal actuator domain. The existences of these two types of shape optimization problems over some class of open sets in general R N space have been proved separately. [ABSTRACT FROM AUTHOR]

Multistimuli responsive materials based on the viologen coordination polymers have attracted much interest in the past few years due to the increasing demand for smart materials. In this paper, based on a viologen ligand 1-(3-carboxybenzyl)- 4,4′-bipyridinium chloride (Hcbbpy) and zinc(II) ion, a new crystalline complex, namely, {[Zn(cbbpy)Cl 2 ]·H 2 O} n (1) has been designed and synthesized. In complex 1 , every cbbpy ligand as a bridge links two Zn2+ ions via carboxylate O atom and pyridine N atom to extend to a 1D zigzag chain. The 1D chains are extended to 3D supramolecular structure through π···π stacking and hydrogen bonding. More importantly, 1 exhibits fast photochromic behaviors in response to UV and X-ray due to the formation of viologen radicals. Complex 1 also shows photo-modulated luminescence property in the solid state. In addition, complex 1 can be deposited on filter paper and displays the potential application as inkless print material. [Display omitted] • A new viologen complex was successfully synthesized and characterized. • Complex 1 shows fast response to UV light and X-ray irradiation. • Complex 1 can be deposited on filter paper and displays as inkless print material. [ABSTRACT FROM AUTHOR]

The active vibration control of a rectangular plate either partially or fully submerged in a fluid was investigated. Piezoelectric sensors and actuators were bonded to the plate, and the assumed mode method was used to derive a dynamic model for the submerged plate. The properties of the piezoelectric actuators and sensors, as well as their coupling to the structure, were used to derive the corresponding equations of their behaviour. The fluid effect was modelled according to the added virtual mass obtained by solving the Laplace equation. The natural vibration characteristics of the plate both in air and in water were obtained theoretically and were found to be consistent with the experimental results, and the changes in the natural frequencies resulting from submersion in fluid can be accurately predicted. A multi-input, multi-output positive position feedback controller was designed by taking the natural vibration characteristics into account and was then implemented by using a digital controller. The experimental results show that piezoelectric sensors and actuators along with the control algorithm can effectively suppress the vibration of a rectangular plate both in air and submerged in a fluid. [ABSTRACT FROM AUTHOR]

SHAPE technology was used to analyze RNA secondary structure of the 5′ most 474 nts of the MHV-A59 genome encompassing the minimal 5′ cis -acting region required for defective interfering RNA replication. The structures generated were in agreement with previous characterizations of SL1 through SL4 and two recently predicted secondary structure elements, S5 and SL5A. SHAPE provided biochemical support for four additional stem–loops not previously functionally investigated in MHV. Secondary structure predictions for 5′ regions of MHV-A59, BCoV and SARS-CoV were similar despite high sequence divergence. The pattern of SHAPE reactivity of in virio genomic RNA, ex virio genomic RNA, and in vitro synthesized RNA was similar, suggesting that binding of N protein or other proteins to virion RNA fails to protect the RNA from reaction with lipid permeable SHAPE reagent. Reverse genetic experiments suggested that SL5C and SL6 within the nsp1 coding sequence are not required for viral replication. [ABSTRACT FROM AUTHOR]

In this paper, we study optimal actuator location of the minimum norm controls for a multi-dimensional heat equation with control defined in the space L 2 ( Ω × ( 0 , T ) ) . The actuator domain is time-varying in the sense that it is only required to have a prescribed Lebesgue measure for any moment. We select an optimal actuator location so that the optimal control takes its minimal norm over all possible actuator domains. We build a framework of finding the Nash equilibrium so that we can develop a sufficient and necessary condition to characterize the optimal relaxed solutions for both actuator location and corresponding optimal control of the open-loop system. The existence and uniqueness of the optimal classical solutions are therefore concluded. As a result, we synthesize both optimal actuator location and corresponding optimal control into a time-varying feedbacks. [ABSTRACT FROM AUTHOR]

[Display omitted] The development and exploration of high-entropy materials with tunable chemical compositions and unique structural characteristics, although challenging, have attracted increasingly greater attention over the past few years. Here, we report a universal and green method to prepare high-entropy layered (oxy)hydroxide (HE-LH) nanosheets under ambient conditions. This method is based on a self-reliant electrochemical process, utilizing only low-cost metal foils and electrolytes as reactant, with no need of involving extra alkali salts and/or organic reagents. Importantly, the composition of HE-LH nanosheets is widely tunable by simply adjusting the combination of metal foils. As a representative example, quinary layered (oxy)hydroxide (CoFeNiCrV-LH) nanosheets are rationally designed, which exhibit superior electrocatalytic activity and long-term durability towards the electrocatalytic oxygen evolution reaction, outperforming both CoFe layered double hydroxides and most previously reported transition-metal-based electrocatalysts. Comprehensive characterization and analysis reveal that the high-entropy effects play a significant role in forming the defect-rich, low-crystalline microstructures, along with large specific surface areas and optimized electronic configurations, thus enabling the boosted electrocatalytic performance. This electrochemical synthetic approach is generally applicable to the scalable synthesis of diverse HE-LH materials towards versatile promising applications. [ABSTRACT FROM AUTHOR]

Sepsis, a complex clinical syndrome characterized by an exaggerated host response to infection, often necessitates hospitalization and intensive care unit admission. Delayed or inaccurate diagnosis of sepsis, coupled with suboptimal treatment strategies, can result in unfavorable outcomes, including mortality. Maresins, a newly discovered family of lipid mediators synthesized from docosahexaenoic acid by macrophages, have emerged as key players in promoting inflammation resolution and the termination of inflammatory processes. Extensive evidence has unequivocally demonstrated the beneficial effects of maresins in modulating the inflammatory response associated with sepsis; however, their bioactivity and functions exhibit remarkable diversity and complexity. This article presents a comprehensive review of recent research on the role of maresins in sepsis, aiming to enhance our understanding of their effectiveness and elucidate the specific mechanisms underlying their actions in sepsis treatment. Furthermore, emerging insights into the management of patients with sepsis are also highlighted. [Display omitted] [ABSTRACT FROM AUTHOR]

Cancer cells frequently develop resistance to chemotherapeutic therapies and targeted drugs, which has been a significant challenge in cancer management. With the growing advances in technologies in isolation and identification of natural products, the potential of natural products in combating cancer multidrug resistance has received substantial attention. Importantly, natural products can impact multiple targets, which can be valuable in overcoming drug resistance from different perspectives. In the current review, we will describe the well-established mechanisms underlying multidrug resistance, and introduce natural products that could target these multidrug resistant mechanisms. Specifically, we will discuss natural compounds such as curcumin, resveratrol, baicalein, chrysin and more, and their potential roles in combating multidrug resistance. This review article aims to provide a systematic summary of recent advances of natural products in combating cancer drug resistance, and will provide rationales for novel drug discovery. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • This work provides quantitative resolution of defect and structural vacancy sites on Al 3 O nodes of MIL-100(Al) and demonstrates the cooperative role of neighboring defect and structural vacancy sites. • Post-treatment of MIL-100(Al) with a formic acid/DMF led to replacement of ligands on defects and extra-framework BTC3- on vacancy sites by formate. • This work illustrates the chemistry of formate, methoxy and hydroxyl ligands on Al 3 O nodes. • The catalytic sites for methanol dehydation are inferred to be two adjacent sites—a defect site and its neighboring vacancy site—with methoxy reaction intermediates bonded on each site. The metal–organic framework (MOF) MIL-100, which incorporates vacancy sites on Al 3 O nodes, was synthesized with various densities of missing-benzene-1,3,5-tricarboxylate (BTC3−)-linker defect sites by using HNO 3 or acetic acid as a modulator. We report data that resolve the effects on reactivity of the node vacancies and defects that are neighbors of each other. For example, extra-framework BTC3− ligands were bonded to one vacancy site per node, and modulator-derived NO 3 − and acetate ligands were bonded in various ratios to defect sites. In reactions with formic acid, these ligands were replaced with monodentate and bidentate formates. The ligands on defects were found to be more reactive than those on vacancies. The MOF was used to catalyze methanol dehydration at 220 °C and 1 bar in a flow reactor, and the catalytic activity increased with increasing numbers of defects and with replacement of extra-framework BTC3- with formate. Catalysis started as methanol reacted with formate ligands to form methyl formate, which desorbed, leaving methoxy groups on the nodes—and these became catalytic reaction intermediates. IR spectra and catalyst performance data show that that catalysis proceeds as bidentate methoxy bonded to a defect site reacts with monodentate methoxy bonded to a neighboring vacancy site. Having a high density of these paired sites, MIL-100(Al) is markedly more active catalytically than the MOF MIL-53, in which these essential sites are mostly isolated. Deactivation of MIL-100 during catalysis resulted from self-inhibition, as bidentate methoxy ligands were replaced with μ 2 -OH ligands formed from water produced in the dehydration reaction. The results highlight the role of pair sites on MOF nodes for catalyzing a reaction that involves a bimolecular step, indicating how to control the catalytic sites. We thus foresee opportunities to tailor MOF catalytic properties for reactions involving various numbers of catalytic sites on the nodes. [ABSTRACT FROM AUTHOR]

[Display omitted] Self-assembly of colloidal nanoparticles (NPs) into well-defined superstructures has been recognized as one of the most promising ways to fabricate rationally-designed functional materials for a variety of applications. Introducing hierarchical mesoporosity into NP superstructures will facilitate mass transport while simultaneously enhancing the accessibility of constituent NPs, which is of critical importance for widening their applications in catalysis and energy-related fields. Herein, we develop a colloidal co-assembly strategy to construct mesostructured, carbon-coated Co 0.5 Fe 2.5 O 4 NP superstructures (M-C@CFOSs), which show great promise as highly efficient electrocatalysts for the oxygen evolution reaction (OER). Specifically, organically-stabilized SiO 2 NPs are employed as both building blocks and sacrificial template, which co-assemble with Co 0.5 Fe 2.5 O 4 NPs to afford binary NP superstructures through a solvent drying process. M-C@CFOSs are obtainable after in situ ligand carbonization followed by the selective removal of SiO 2 NPs. The hierarchical mesoporous structure of M-C@CFOSs, combined with the conformal graphitic carbon coating derived from the native organic ligands, significantly improves their electrocatalytic performance as OER electrocatalysts when compared with nonporous Co 0.5 Fe 2.5 O 4 NP superstructures. This work establishes a new and facile approach for designing NP superstructures with hierarchical mesoporosity, which may find wide applications in energy storage and conversion. [ABSTRACT FROM AUTHOR]

The influence of perovskite components on the morphology, optical absorption and photovoltaic performances are systematically investigated. The results reveal that the surface and grain sizes of mixed perovskite film become rougher and larger with increasing FAI concentration. In the meanwhile, the formation of δ-FAPbI 3 is successfully inhibited. As a result, the efficiency of perovskite solar cells based on mixed absorbers is improved by about 27% compared to pristine MAI based perovskite devices. The absorption layer is a crucial factor for high-performance perovskite solar cells. In this work, the influence of the two components, methylammonium iodide (MAI) and formamidinium iodide (FAI) on the morphology, optical absorption and photovoltaic performances was systematically investigated. The results revealed that the surface morphologies of MAI/FAI based perovskite films were rougher, and the grain sizes became larger with increasing the FAI concentration. UV–Vis and photoluminescence spectra showed that there was a red shift with enhancing the FAI concentration. By the effective doping of FAI into the pristine MAI based perovskite film, the formation of a δ-FAPbI 3 was successfully inhibited. As a result, the power conversion efficiency (PCE) of the perovskite solar cells based on mixed absorption layers was improved by about 27% compared to the pristine MAI based perovskite device. [ABSTRACT FROM AUTHOR]

A new method relying on machine learning and resistivity to predict concentrations of petroleum hydrocarbon pollution in soil was proposed as a means of investigation and monitoring. Currently, determining pollutant concentrations in soil is primarily achieved through costly sampling and testing of numerous borehole samples, which carries the risk of further contamination by penetrating the aquifer. Additionally, conventional petroleum hydrocarbon geophysical surveys struggle to establish a correlation between survey results and pollutant concentration. To overcome these limitations, three machine learning models (KNN, RF, and XGBOOST) were combined with the geoelectrical method to predict petroleum hydrocarbon concentrations in the source area. The results demonstrate that the resistivity-based prediction method utilizing machine learning is effective, as validated by R-squared values of 0.91 and 0.94 for the test and validation sets, respectively, and a root mean squared error of 0.19. Furthermore, this study confirmed the feasibility of the approach using actual site data, along with a discussion of its advantages and limitations, establishing it as an inexpensive option to investigate and monitor changes in petroleum hydrocarbon concentration in soil. • The prediction of soil petroleum hydrocarbon concentration is achieved by machine learning and resistivity tomography method. • Building the mapping relationship between soil petroleum hydrocarbon pollution concentration and resistivity. • External validation data verify feasibility of predicting soil petroleum hydrocarbon contamination concentrations based on resistivity. [ABSTRACT FROM AUTHOR]

The blockchain whitepaper contains detailed technical and business information, so its analysis is important for blockchain text mining. Previous works focus on analyze homogeneous objects and relations. The main problem, however, is these works do not take into account the heterogeneity of information. This paper presents a new methodology for whitepapers analysis by designing heterogeneous graph neural network, named S-HGNN. In detail, this paper first builds a Heterogeneous Information Network (HIN) using heterogeneous objects and relationships extracted from the whitepaper to obtain similarity measures, then uses Graph Convolutional Network (GCN) and Graph Attention Network (GAT) to integrate both structural information and internal semantic into the whitepaper embedding. Compared with the previous models, this model improves 0.96% ∼ 33.34% in terms of F1-score for classification task, and 4.94% ∼ 14.14% in terms of purity for clustering task, and gets stable results on different tasks. The results show the effectiveness and robustness of this model for whitepapers analysis. • We propose a novel automatic blockchain whitepapers analysis framework which integrates both popular data mining and deep learning techniques for intelligent analysis of whitepapers about blockchain products. • This paper explores a heterogeneous Graph Neural Network based on GCN and GAT, and applies the learned feature of whitepapers into clustering and classification tasks. [ABSTRACT FROM AUTHOR]

Aldol condensation of cycloketone(s) is an efficient reaction path to synthesize polycyclic compounds via C C bond formation. In this work, aldol condensation of cyclopentanone and/or cyclohexanone over monoclinic ZrO 2 has been investigated by combination of experiments and DFT calculations. Both self-condensation and cross-condensation of cyclopentanone and/or cyclohexanone were carried out at 130 °C in a solvent-free condition under atmospheric pressure. Reactant selectivity and product distribution were analyzed. DFT calculations were performed to investigate the mechanism and reactant selectivity of cycloketone condensation on ZrO 2 , showing the favored cross-condensation between cyclopentanone and cyclohexanone is ascribed to the formation of a metastable state of a seven-membered ring that lowers activation barrier during C C bond formation. [ABSTRACT FROM AUTHOR]

Surjective homological epimorphisms with stratifying kernel can be used to construct recollements of derived module categories. These ‘stratifying’ recollements are derived from recollements of module categories. Can every recollement be put in this form, up to equivalence? A negative answer will be given after providing a characterisation of recollements equivalent to stratifying ones. Moreover, criteria for a ring epimorphism to be ‘stratifying’ will be presented as well as constructions of such epimorphisms. [ABSTRACT FROM AUTHOR]

Recollements of derived module categories are investigated, using a new technique, ladders of recollements, which are maximal mutation sequences. The position in the ladder is shown to control whether a recollement restricts from unbounded to another level of derived category. Ladders also turn out to control derived simplicity on all levels. An algebra is derived simple if its derived category cannot be deconstructed, that is, if it is not the middle term of a non-trivial recollement whose outer terms are again derived categories of algebras. Derived simplicity on each level is characterised in terms of heights of ladders. These results are complemented by providing new classes of examples of derived simple rings, in particular indecomposable commutative rings, as well as by a finite dimensional counterexample to the Jordan–Hölder problem for derived module categories. Moreover, recollements are used to compute homological and K-theoretic invariants. [ABSTRACT FROM AUTHOR]

Changes in land use and landscapes have a direct impact on the regional eco-environment. It is of great importance to understand the change pattern of land use, landscapes, and their mechanism on the ecological quality, especially ecologically fragile areas. The northern sand-prevention belt (NSPB) is an important ecologically fragile area in China, which has a large influence on the ecological security of the entire country. Based on the land use data of the NSPB in 2000, 2010, and 2018, we studied the spatio-temporal characteristics of land-use change and change in landscape patterns. The ecological quality represented by the remote sensing-based desertification index (RSDI) was calculated using satellite images. The effects of land use and landscape patterns on RSDI were analyzed by geographic detector and geographically weighted regression. Important results include the following: (1) Land-use change in the study area was high during 2000–2010 but slower in 2010–2018. Grassland was the largest land-use type in the NSPB, and varied greatly in terms of total change and spatial location. The major change was the conversion between dense and moderate grass, with 64,860 km2 of dense grass turning into moderate grass, and 48,505 km2 changing the other way. (2) Among the four landscape metrics, patch density, area-weighted mean fractal dimension, and edge density increased, whereas the aggregation index decreased, which indicated that the landscape was developing towards heterogeneity, fragmentation, complexity, and aggregation. Spatially, the landscape metrics presented a strip distribution in the east of the NSPB. (3) The effects of various land-use types on ecological quality, from high to low, were unused land, woodland, dense grass, cropland, moderate grass, built-up land, sparse grass, and waterbody. The areas where the ecological quality was greatly affected by the landscape patterns were concentrated in the agro-pastoral ecotone and the forest-steppe ecotone. The results of this study reveal the trends of land use and landscape patterns in the NSPB over 18 years and can help to understand their mechanism on ecological quality, which is of significance for the management of this area. • LUC in the NSPB was active from 2000 to 2010 and weakened from 2010 to 2018. • The landscape was developing towards heterogeneity, fragmentation, complexity, and aggregation. • The effects of land use and landscape on ecological quality were studied by GD and GWR. [ABSTRACT FROM AUTHOR]