ABSTRACT
Developing high-efficiency and stable bifunctional electrocatalysts for water splitting remains a great challenge. Herein, NiMoO4 nanowires as sacrificial templates to synthesize Mo-doped NiFe Prussian blue analogs are employed, which can be easily phosphorized to Mo-doped Fe2xNi2(1-x)P nanotubes (Mo-FeNiP NTs). This synthesis method enables the controlled etching of NiMoO4 nanowires that results in a unique hollow nanotube architecture. As a bifunctional catalyst, the Mo-FeNiP NTs present lower overpotential and Tafel slope of 151.3 (232.6) mV at 100 mA cm-2 and 76.2 (64.7) mV dec-1 for HER (OER), respectively. Additionally, it only requires an ultralow cell voltage of 1.47 V to achieve 10 mA cm-2 for overall water splitting and can steadily operate for 200 h at 100 mA cm-2. First-principles calculations demonstrate that Mo doping can effectively adjust the electron redistribution of the Ni hollow sites to optimize the hydrogen adsorption-free energy for HER. Besides, in situ Raman characterization reveals the dissolving of doped Mo can promote a rapid surface reconstruction on Mo-FeNiP NTs to dynamically stable (Fe)Ni-oxyhydroxide layers, serving as the actual active species for OER. The work proposes a rational approach addressed by electron manipulation and surface reconstruction of bimetallic phosphides to regulate both the HER and OER activity.
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CO plays a crucial role as an intermediate in electrochemical CO2 conversion to generate multicarbon (C2+) products. However, optimizing the coverage of the CO intermediate (*CO) to improve the selectivity of C2+ products remains a great challenge. Here, we designed a hierarchically structured double hollow spherical nanoreactor featuring atomically dispersed nickel (Ni) atoms as the core and copper (Cu) nanoparticles as the shell, which can greatly improve the catalytic activity and selectivity for C2+ compounds. Within this configuration, CO generated at the active Ni sites on the inner layer accumulates in the cavity before spilling over neighboring Cu sites on the outer layer, thus enhancing CO dimerization within the cavity. Notably, this setup achieves a sustained faradaic efficiency of 74.4% for C2+ production, with partial current densities reaching 337.4 mA cm-2. In situ Raman spectroscopy and finite-element method (FEM) simulations demonstrate that the designed local CO generator can effectively increase the local CO concentration and restrict CO evolution, ultimately boosting C-C coupling. The hierarchically ordered architectural design represents a promising solution for achieving highly selective C2+ compound production in the electroreduction of CO2.
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Singlet oxygen (term symbol 1Δg, hereafter 1O2), a reactive oxygen species, has recently attracted increasing interest in the field of rechargeable batteries and electrocatalysis and photocatalysis. These sustainable energy conversion and storage technologies are of vital significance to replace fossil fuels and promote carbon neutrality and finally tackle the energy crisis and climate change. Herein, the recent progresses of 1O2 for energy storage and conversion is summarized, including physical and chemical properties, formation mechanisms, detection technologies, side reactions in rechargeable batteries and corresponding inhibition strategies, and applications in electrocatalysis and photocatalysis. The formation mechanisms and inhibition strategies of 1O2 in particular aprotic lithium-oxygen (Li-O2) batteries are highlighted, and the applications of 1O2 in photocatalysis and electrocatalysis is also emphasized. Moreover, the confronting challenges and promising directions of 1O2 in energy conversion and storage systems are discussed.
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Non-dissociative chemisorption solid-state storage of hydrogen molecules in host materials is promising to achieve both high hydrogen capacity and uptake rate, but there is the lack of non-dissociative hydrogen storage theories that can guide the rational design of the materials. Herein, we establish generalized design principle to design such materials via the first-principles calculations, theoretical analysis and focused experimental verifications of a series of heteroatom-doped-graphene-supported Ca single-atom carbon nanomaterials as efficient non-dissociative solid-state hydrogen storage materials. An intrinsic descriptor has been proposed to correlate the inherent properties of dopants with the hydrogen storage capability of the carbon-based host materials. The generalized design principle and the intrinsic descriptor have the predictive ability to screen out the best dual-doped-graphene-supported Ca single-atom hydrogen storage materials. The dual-doped materials have much higher hydrogen storage capability than the sole-doped ones, and exceed the current best carbon-based hydrogen storage materials.
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Background: Accelerated modern industrial processes, extensive use of pesticides and fertilizers and remaining issues of wastewater irrigation have led to an increasingly severe composite pollution of heavy metals in arable land. Soil contamination can cause significant damage to ecological environments and human health. Mineral resource mining can result in varying degrees of heavy metal pollution in surrounding water systems and soil. As a plateau lake, Hongfeng Lake has a fragile watershed ecosystem. Coupled with the rapid development of the current socio-economy and the ongoing activities of mining, urbanization and agricultural development, the water and soil environment of the lake and arable land are facing serious heavy metal pollution. Therefore, the situation warrants attention. Methods: This study focused on characterizing soil types and conducted sampling and laboratory testing on the farmland soil in Hongfeng Lake. The integrated Nemero comprehensive pollution assessment and potential ecological pollution assessment methods were used to evaluate the heavy metal pollution status. The APCS-MLR model was employed to explore the sources of heavy metal pollution. In addition, the human health risk model was used to analyze the association between heavy metal content in cultivated land and human health risks. Results: The single-factor pollution of each element was ranked in descending order: Hg > As > Pb > Cr > Cd, with Hg being the main pollutant factor. The entire area was subjected to mild pollution according to the pollution index. Pollution source analysis indicated two main pollution sources. Hg, As, Pb and Cr pollution mainly resulted from Source 1 (industrial and natural activities), accounting for 71.99%, 51.57%, 67.39% and 68.36%, respectively. Cd pollution was mainly attributed to Source 2 (agricultural pollution source), contributing 84.12%. The health risk assessment model shows that heavy metals posed acceptable carcinogenic risks to humans rather than non-carcinogenic risks. As was the main non-carcinogenic risk factor, while Cr was the main carcinogenic risk factor, with higher risks in children than adults. Conclusion: Our study identified the heavy metal pollution in farmland soil in Hongfeng Lake, evaluated and analyzed the pollution sources and identified the heavy metal elements in cultivated lands that have the greatest impact on human health risks. The aim of this study is to provide a scientific basis for soil heavy metal pollution control.
Subject(s)
Mercury , Metals, Heavy , Adult , Child , Humans , Soil , Ecosystem , Environmental Monitoring , Cadmium , Lakes , Lead , Agriculture , Metals, Heavy/analysis , Risk Assessment , China , WaterABSTRACT
The fundamental purpose of this study is to conduct an inquiry into the efficacy of China's green credit strategy, and that will be the core focus of the investigation. As part of this study, we investigate whether or not businesses that increase the environmental transparency of their operations to the outside world and green innovation within their operations are rewarded with more favorable bank loan terms as a direct result of receiving green credit. Specifically, we look at whether or not these businesses are awarded green credit. Our hypothesis is put to the test by using the difference-in-differences (DID) model and the data that was collected from a sample of 1086 publicly traded Chinese manufacturers over the years 2012 to 2017. According to the data, businesses that improve the quality of their environmental disclosures do not receive an increase in their access to corporate finance. On the other hand, businesses that introduce new environmentally friendly breakthroughs do receive an increase in their access to corporate finance. Our research demonstrates that the root of the problem is corporate green-washing, a practice that is common in regions with low environmental disclosure standards and makes it more difficult for businesses to obtain new loans. This practice is popular in areas where environmental disclosure standards are lax. This is the most basic explanation for why the phenomena occur in the first place. Our findings contribute to the literature on themes including green credit policy, corporate green innovation, environmental transparency, and green-washing, all of which are useful to corporations, governments, and financial institutions.
Subject(s)
Awards and Prizes , Environmental Policy , Humans , China , Commerce , Disclosure , PolicyABSTRACT
The identification of heavy metal sources in farmland soils is essential for the rational health condition management and sustainable development of soil. Using source resolution results(source component spectrum and source contribution)of a positive matrix factorization(PMF)model, historical survey data, and time-series remote sensing data, integrating a geodetector(GD), an optimal parameters-based geographical detector(OPGD), a spatial association detector(SPADE), and an interactive detector for spatial associations(IDSA)model, this study explored the modifiable areal unit problem(MAUP) of spatial heterogeneity of soil heavy metal sources and identified the driving factors and their interacting effects on the spatial heterogeneity of soil heavy metal sources in categorical and continuous variables, respectively. The results showed that the spatial heterogeneity of soil heavy metal sources at small and medium scales was affected by the spatial scale, and the optional spatial unit was 0.08 km2 for detecting spatial heterogeneity of soil heavy metal sources in the study region. Considering spatial correlation and discretization level, the combination of the quantile method and discretization parameters with an interruption number of 10 could be implied to reduce the partitioning effects on continuous variables in the detection of spatial heterogeneity of soil heavy metal sources. Within categorical variables, strata(PD 0.12-0.48) controlled the spatial heterogeneity of soil heavy metal sources, the interaction between strata and watersheds explained 27.28%-60.61% of each source, and the high-risk areas of each source were distributed in the lower sinian system, upper cretaceous in strata, mining land in land use, and haplic acrisols in soil types. Within continuous variables, population (PSD 0.40-0.82) controlled the spatial variation in soil heavy metal sources, and the explanatory power of spatial combinations of continuous variables for each source ranged from 61.77% to 78.46%. The high-risk areas of each source were distributed in evapotranspiration (41.2-43 kg·m-2), distance from the river (315-398 m), enhanced vegetation index (0.796-0.995), and distance from the river (499-605 m). The results of this study provide a reference for the research of the drivers of heavy metal sources and their interactions in arable soils and provide an important scientific basis for the management of arable soil and its sustainable development in karst areas.
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As a straightforward way to fix solar energy, photo/photothermal catalysis with semiconductor provides a promising way to settle the energy shortage and environmental crisis in many fields, especially in clean energy conversion. Topologically porous heterostructures (TPHs), featured with well-defined pores and mainly composed by the derivatives of some precursors with specific morphology, are a major part of hierarchical materials in photo/photothermal catalysis and provide a versatile platform to construct efficient photocatalysts for their enhanced light absorption, accelerated charges transfer, improved stability, and promoted mass transportation. Therefore, a comprehensive and timely review on the advantages and recent applications of the TPHs is of great importance to forecast the potential applications and research trend in the future. This review initially demonstrates the advantages of TPHs in photo/photothermal catalysis. Then the universal classifications and design strategies of TPHs are emphasized. Besides, the applications and mechanisms of photo/photothermal catalysis in hydrogen evolution from water splitting and COx hydrogenation over TPHs are carefully reviewed and highlighted. Finally, the challenges and perspectives of TPHs in photo/photothermal catalysis are also critically discussed.
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Al ion batteries (AIBs) are attracting considerable attention owing to high volumetric capacity, low cost, and high safety. However, the strong electrostatic interaction between Al3+ and host lattice leads to discontented cycling life and inferior rate capability. Herein, a new strategy of employing water molecules contained VOPO4 ·H2 O to boost Al3+ migration via the charge shielding effect of water is reported. It is revealed that VOPO4 ·H2 O with water lubrication effect and smaller steric hindrance owns high capacity and fast Al3+ diffusion, while the loss of unstable water upon cycling leads to a rapid performance degradation. To address this problem, ultrathin VOPO4 ·H2 O@MXene nanosheets are fabricated via the formed TiOV bond between VOPO4 ·H2 O and MXene. The MXene aided exfoliation results in enhanced VOwater bond strength between H2 O and VOPO4 that endows the obtained composite with strong water holding ability, contributing to the extraordinary cycling stability. Consequently, the VOPO4 ·H2 O@MXene delivers a high discharge potential of 1.8 V and maintains discharge capacities of 410 and 374.8 mAh g-1 after 420 and 2000 cycles at the current densities of 0.5 and 1.0 A g-1 , respectively. This work provides a new understanding of water-contained AIBs cathodes and vital guidance for developing high-performance AIBs.
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Direct hydrogenation of CO2 to methanol using green hydrogen has emerged as a promising method for carbon neutrality, but qualifying catalysts represent a grand challenge. In2 O3 /ZrO2 catalyst has been extensively applied in methanol synthesis due to its superior activity; however, the electronic effect by strong oxides-support interactions between In2 O3 and ZrO2 at the In2 O3 /ZrO2 interface is poorly understood. In this work, abundant In2 O3 /ZrO2 heterointerfaces are engineered in a hollow-structured In2 O3 @ZrO2 heterostructure through a facile pyrolysis of a hybrid metal-organic framework precursor MIL-68@UiO-66. Owing to well-defined In2 O3 /ZrO2 heterointerfaces, the resultant In2 O3 @ZrO2 exhibits superior activity and stability toward CO2 hydrogenation to methanol, which can afford a high methanol selectivity of 84.6% at a conversion of 10.4% at 290 °C, and 3.0 MPa with a methanol space-time yield of up to 0.29 gMeOH gcat -1 h-1 . Extensive characterization demonstrates that there is a strong correlation between the strong electronic In2 O3 -ZrO2 interaction and catalytic selectivity. At In2 O3 /ZrO2 heterointerfaces, the electron tends to transfer from ZrO2 to In2 O3 surface, which facilitates H2 dissociation and the hydrogenation of formate (HCOO*) and methoxy (CH3 O*) species to methanol. This study provides an insight into the In2 O3 -based catalysts and offers appealing opportunities for developing heterostructured CO2 hydrogenation catalysts with excellent activity.
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Selective hydrogenation of CO2 to methanol is a "two birds, one stone" technology to mitigate the greenhouse effect and solve the energy demand-supply deficit. Cu-based catalysts can effectively catalyze this reaction but suffer from low catalytic stability caused by the sintering of Cu species. Here, we report a series of zeolite-fixed catalysts Cu/ZnOx(Y)@Na-ZSM-5 (Y is the mass ratios of Cu/Zn in the catalysts) with core-shell structures to overcome this issue and strengthen the transformation. Fascinatingly, in this work, we first employed bimetallic metal-organic framework, CuZn-HKUST-1, nanoparticles (NPs) as a sacrificial agent to introduce ultrasmall Cu/ZnOx NPs (â¼2 nm) into the crystalline particles of the Na-ZSM-5 zeolite via a hydrothermal synthesis method. The catalytic results showed that the optimized zeolite-encapsulated Cu/ZnOx(1.38)@Na-ZSM-5 catalyst exhibited the space time yield of methanol (STYMeOH) of 44.88 gMeOH·gCu-1·h-1, much more efficient than the supported Cu/ZnOx/Na-ZSM-5 catalyst (13.32 gMeOH·gCu-1·h-1) and industrial Cu/ZnO/Al2O3 catalyst (8.46 gMeOH·gCu-1·h-1) under identical conditions. Multiple studies demonstrated that the confinement in the zeolite formwork affords an intimate surrounding for the active phase to create synergies and avoid the separation of Cu-ZnOx interfaces, which results in an improved performance. More importantly, in the long-term test, the Cu/ZnOx(1.38)@Na-ZSM-5 catalyst exhibited constant STYMeOH with superior durability benefitted from its fixed structure. The current findings demonstrate the importance of confinement effects in designing highly efficient and stable methanol synthesis catalysts.
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As a chronic degenerative joint disease, the characteristics of osteoarthritis (OA) are degeneration of articular cartilage, subchondral bone sclerosis and bone hyperplasia. It has been reported that microRNA (miR)1865p serves a key role in the development of various tumors, such as osteosarcoma, nonsmallcell lung cancer cells, glioma and colorectal cancer. The present study aimed to investigate the effect of miR1865p in OA. Different concentrations of IL1ß were used to treat the human chondrocyte cell line CHON001 to simulate inflammation, and CHON001 cell injury was assessed by detecting cell viability, apoptosis, caspase-3 activity and the levels of TNFα, IL8 and IL6. Subsequently, reverse transcriptionquantitative PCR was performed to measure miR1865p expression. The results demonstrated that following IL1ß treatment, CHON001 cell viability was suppressed, apoptosis was promoted, the caspase-3 activity was significantly enhanced and the release of TNFα, IL8 and IL6 was increased. In addition, IL1ß treatment significantly upregulated miR1865p expression in CHON001 cells. It was also identified that MAPK1 was a target gene of miR1865p, and was negatively regulated by miR1865p. miR186 inhibitor and MAPK1small interfering RNA (siRNA) were transfected into CHON001 cells to investigate the effect of miR1865p on CHON001 cell injury induced by IL1ß. The results demonstrated that miR186 inhibitor suppressed the effects of IL1ß on CHON001 cells, and these effects were reversed by MAPK1siRNA. In conclusion, the present results indicated that miR1865p could attenuate IL1ßinduced chondrocyte inflammation damage by increasing MAPK1 expression, suggesting that miR1865p may be used as a potential therapeutic target for OA.
Subject(s)
Chondrocytes/metabolism , Down-Regulation , MicroRNAs/biosynthesis , Osteoarthritis/metabolism , Cell Line , Chondrocytes/pathology , Cytokines/metabolism , Humans , Mitogen-Activated Protein Kinase 1 , Osteoarthritis/pathologyABSTRACT
The design and development of efficient catalytic materials with synergistic catalytic sites always has long been known to be a thrilling and very dynamic research field. Crystalline porous materials (CPMs) mainly including metal-organic frameworks and zeolites with high scientific and industrial impact have recently been the subject of extensive research due to their essential role in modern chemical industrial processes. The rational incorporation of guest species in CPMs can synergize the respective strengths of these components and allow them to collaborate with each other for synergistic catalysis, leading to enhanced catalytic activity, selectivity, and stability in a broad range of catalytic processes. In this review, the recent advances in the development of CPMs-confined active metal species, including metal nanoparticles, metal/metal oxides heteroparticles, metal oxide, subnanometric metal clusters, and polyoxometalates, for heterogeneous catalysis, with a particular focus on synergistic effects between active components that result in an enhanced performance are highlighted. Insights into catalysts design strategies, host-guest interactions, and structure-property relationships have been illustrated in detail. Finally, the existing challenges and possible development directions in CPMs-based encapsulation-structured synergistic catalysts are discussed.
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BACKGROUND: The most common complication of oblique lumbar interbody fusion (OLIF) is endplate fracture/subsidence. The mechanics of endplate fracture in OLIF surgery are still unclear. The aim of the present study was to evaluate the biomechanical stability in patients undergoing OLIF surgery with stand-alone (SA) and bilateral pedicle screw fixation (BPSF) methods. METHODS: A finite element model of the L1-L5 spinal unit was established and validated. Using the validated model technique, L4-L5 functional surgical models corresponding to the SA and BPSF methods were created. Simulations using the models were performed to investigate OLIF surgery. A 500-N compression force was applied to the superior surface of the model to represent the upper body weight, and a 7.5-Nm moment was applied to simulate the 6 movement directions of the lumbar spinal model: flexion and extension, right and left lateral bending, and right and left axial rotation. Finite element models were developed to compare the biomechanics of the SA and BPSF groups. RESULTS: Compared with the range of motion of the intact lumbar model, that of the SA model was decreased by 79.6% in flexion, 54.5% in extension, 57.2% in lateral bending, and 50.0% in axial rotation. The BPSF model was decreased by 86.7% in flexion, 77.3% in extension, 76.2% in lateral bending, and 75.0% in axial rotation. Compared with the BPSF model, the maximum stresses of the L4 inferior endplate and L5 superior endplate were greatly increased in the SA model. The L4 inferior endplate stress was increased to 49.7 MPa in extension, and the L5 superior endplate stress was increased to 47.7 MPa in flexion, close to the yield stress of the lamellar bone (60 MPa). CONCLUSIONS: OLIF surgery with BPSF could reduce the maximum stresses on the endplate, which might reduce the incidence of cage subsidence. OLIF surgery with the SA method produced more stress compared with BPSF, especially in extension and flexion, which might be a potential risk factor for cage subsidence.
Subject(s)
Finite Element Analysis , Lumbar Vertebrae/surgery , Lumbosacral Region/surgery , Pedicle Screws , Biomechanical Phenomena/physiology , Humans , Lumbar Vertebrae/pathology , Lumbosacral Region/pathology , Models, Anatomic , Range of Motion, Articular/physiology , Spinal Fusion/methodsABSTRACT
The separation and purification of light hydrocarbons (LHs) mixtures is one of the most significantly important but energy demanding processes in the petrochemical industry. As an alternative technology to energy intensive traditional separation methods, such as distillation, absorption, extraction, etc., adsorptive separation using selective solid adsorbents could potentially not only lower energy cost but also offer higher efficiency. The need to develop solid materials for the efficiently selective adsorption of LHs molecules, under mild conditions, is therefore of paramount importance and urgency. Metal-organic frameworks (MOFs), emerging as a relatively new class of porous organic-inorganic hybrid materials, have shown promise for addressing this challenging task due to their unparalleled features. Herein, recent advances of using MOFs as separating agents for the separation and purification of LHs, including the purification of CH4 , and the separations of alkynes/alkenes, alkanes/alkenes, C5 -C6 -C7 normal/isoalkanes, and C8 alkylaromatics, are summarized. The relationships among the structural and compositional features of the newly synthesized MOF materials and their separation properties and mechanisms are highlighted. Finally, the existing challenges and possible research directions related to the further exploration of porous MOFs in this very active field are also discussed.
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Solid-liquid separation of similarly sized organic molecules utilizing sorbents offers the potential for new energy-efficient approaches to a number of important industrial separations such as xylenes (C8) separations. Research on selective C8 sorption has tended to focus upon rigid porous materials such as zeolites and MOFs but has revealed generally weak selectivity that is inconsistent across the range of C8 molecules. Nevertheless, there are a few recent examples of non-porous molecular materials that exhibit relatively high selectivity for p-xylene (pX) from pX/oX, approaching that of the current benchmark pX sorbent, the zeolite H/ZSM-5. Herein, we report that a L-shaped Ag(i) complex, AgLClO4 (M), which crystallizes as a non-porous molecular solid material, offering exceptional performance for pX selectivity across the range of C8 isomers with liquid extraction selectivity values of 24.0, 10.4 and 6.2 vs. oX, eB and mX, respectively. The pX selectivities over oX and eB are among the highest yet reported. Moreover, M also exhibits strong vapor extraction selectivity and can be regenerated by exposure to vacuum drying.