•The review about speciation analysis of HMCs is important but scarce.•Prevalent methods for aqueous HMC mitigation were introduced.•Technologies for aqueous HMC analysis were summarized and ...discussed.•The importance role of species transformation in HMC decomplexation was elucidated.•Outlook and perspective were provided based on current challenges.
Efficient mitigation of toxic and recalcitrant heavy metal complexes (HMCs) from water and wastewater is critical to guarantee the environmental health and safety, but still faces many challenges. Although a number of techniques have been developed to deal with HMCs laden water/wastewater, there is still a lack of comprehensive and insightful understanding of the relevant mechanisms. One of the main reasons is the complicated heavy metal speciation in water/wastewater, which masks the speciation distribution and coordination circumstance of heavy metals. In this review, prevalent methods for HMC elimination (e.g., physical separation and chemical decomplexation) are briefly presented and evaluated. Especially, the characterization methods of HMCs, which afford to provide valuable information on the speciation distribution of heavy metals, are underlined and discussed. Furthermore, typical cases are provided to elucidate the essential role of species transformation in the decomplexation of HMCs and the implications for enhanced mitigation of HMCs are also discussed. Finally, the current challenges and perspectives for future study in this field are proposed.
Photocatalytic CO2 conversion into solar fuels is a promising technology to alleviate CO2 emissions and energy crises. The development of core‐shell structured photocatalysts brings many benefits to ...the photocatalytic CO2 reduction process, such as high conversion efficiency, sufficient product selectivity, and endurable catalyst stability. Core‐shell nanostructured materials with excellent physicochemical features take an irreplaceable position in the field of photocatalytic CO2 reduction. In this review, the recent development of core‐shell materials applied for photocatalytic reduction of CO2 is introduced. First, the basic principle of photocatalytic CO2 reduction is introduced. In detail, the classification and synthesis techniques of core‐shell catalysts are discussed. Furthermore, it is also emphasized that the excellent properties of the core‐shell structure can greatly improve the activity, selectivity, and stability in the process of photocatalytic CO2 reduction. Hopefully, this paper can provide a favorable reference for the preparation of efficient photocatalysts for CO2 reduction.
This review summarizes the recent development of core‐shell materials applied for photocatalytic reduction of CO2, including its catalytic function, adsorption performance, and light responsiveness. The advantages of these materials for photocatalytic CO2 reduction are highlighted.
Photocatalytic CO2 reduction technology has a broad potential for dealing with the issues of energy shortage and global warming. As a widely studied material used in the photocatalytic process, ...titanium dioxide (TiO2) has been continuously modified and tailored for more desirable application. Recently, the defective/reduced titanium dioxide (TiO2−x) catalyst has attracted broad attention due to its excellent photocatalytic performance for CO2 reduction. In this perspective review, we comprehensively present the recent progress in TiO2−x-based materials for photocatalytic CO2 reduction. In detail, the review starts with the fundamentals of CO2 photocatalytic reduction. Then, the synthesis of a defective TiO2 structure is introduced for the regulation of its photocatalytic performance, especially its optical properties and dissociative adsorption properties. In addition, the current application of TiO2−x-based photocatalysts for CO2 reduction is also highlighted, such as metal–TiO2−x, oxide–TiO2−x and TiO2−x–carbon-based photocatalysts. Finally, the existing challenges and possible scope of photocatalytic CO2 reduction over TiO2−x-based materials are discussed. We hope that this review can provide an effective reference for the development of more efficient and reasonable photocatalysts based on TiO2−x.
Direct allylic C−H thiolation is straightforward for allylic C(sp3)−S bond formation. However, strong interactions between thiol and transition metal catalysts lead to deactivation of the catalytic ...cycle or oxidation of sulfur atom under oxidative condition. Thus, direct allylic C(sp3)−H thiolation has proved difficult. Represented herein is an exceptional for direct, efficient, atom‐ and step‐economic thiolation of allylic C(sp3)−H and thiol S−H under visible light irradiation. Radical trapping experiments and electron paramagnetic resonance (EPR) spectroscopy identified the allylic radical and thiyl radical generated on the surface of photocatalyst quantum dots (QDs). The C−S bond formation does not require external oxidants and radical initiators, and hydrogen (H2) is produced as byproduct. When vinylic C(sp2)−H was used instead of allylic C(sp3)−H bond, the radical‐radical cross‐coupling of C(sp2)−H and S−H was achieved with liberation of H2. Such a unique transformation opens up a door toward direct C−H and S−H coupling for valuable organosulfur chemistry.
A direct, efficient, atom‐ and step‐economic thiolation of allylic C(sp3)−H or vinylic C(sp2)−H with thiol S−H is reported for the first time. The radical–radical cross‐coupling of allylic C(sp3)−H or vinylic C(sp2)−H with thiol S−H is achieved with liberation of H2. Such a unique transformation opens up a door toward direct cross‐coupling of C−H and S−H bonds in valuable organosulfur chemistry.
Converting CO2 to renewable fuels or valuable carbon compounds is an effective way to solve the global warming and energy crisis. Compared with other CO2 conversion methods, photocatalytic reduction ...of CO2 is more energy-saving, environmentally friendly, and has a broader application prospect. Layered double hydroxide (LDH) has attracted widespread attention as a two-dimensional material, composed of metal hydroxide layers, interlayer anions and water molecules. This review briefly introduces the basic theory of photocatalysis and the mechanism of CO2 reduction. The composition and properties of LDH are introduced. The research progress on LDH in the field of photocatalytic reduction of CO2 is elaborated from six aspects: directly as a catalyst, as a precursor for a catalyst, and by modification, intercalation, supporting with other materials and construction of a heterojunction. Finally, the development prospects of LDH are put forward. This review could provide an effective reference for the development of more efficient and reasonable photocatalysts based on LDH.
A bis(pyridyl)amine‐bipyridine‐iron(II) framework (Fe(BPAbipy)) of complexes 1–3 is reported to shed light on the multistep nature of CO2 reduction. Herein, photocatalytic conversion of CO2 to CO ...even at low CO2 concentration (1 %), together with detailed mechanistic study and DFT calculations, reveal that 1 first undergoes two sequential one‐electron transfer affording an intermediate with electron density on both Fe and ligand for CO2 binding over proton. The following 2 H+‐assisted Fe‐CO formation is rate‐determining for selective CO2‐to‐CO reduction. A pendant, proton‐shuttling α‐OH group (2) initiates PCET for predominant H2 evolution, while an α‐OMe group (3) cancels the selectivity control for either CO or H2. The near‐unity selectivity of 1 and 2 enables self‐sorting syngas production at flexible CO/H2 ratios. The unprecedented results from one kind of molecular catalyst skeleton encourage insight into the beauty of advanced multi‐electron and multi‐proton transfer processes for robust CO2RR by photocatalysis.
A polypyridine Fe‐based skeleton is reported for selective CO2‐to‐CO photoreduction even under 1 % CO2. Mechanistic insights reveal two sequential one‐electron transfer affording an intermediate with delocalized electron density on both Fe and ligand for CO2 addition. Proton‐assisted CO formation is crucial for CO2 reduction. A pendant, proton‐shuttling α‐OH group switches the transformation to H2 exclusively, which enables self‐sorting syngas formation at flexible CO/H2 ratios.
The main cause of high mortality from sepsis is that immunosuppression leads to life-threatening organ dysfunction, and reversing immunosuppression is key to sepsis treatment. Interferon γ (IFNγ) is ...a potential therapy for immunosuppression of sepsis, promoting glycolysis to restore metabolic defects in monocytes, but the mechanism of treatment is unclear.
To explore the immunotherapeutic mechanism of IFNγ, this study linked the Warburg effect (aerobic glycolysis) to immunotherapy for sepsis and used cecal ligation perforation (CLP) and lipopolysaccharide (LPS) to stimulate dendritic cells (DC) to establish in vivo and in vitro sepsis models, Warburg effect inhibitors (2-DG) and PI3K pathway inhibitors (LY294002) were used to explore the mechanism by which IFNγ regulates immunosuppression in mice with sepsis through the Warburg effect.
IFNγ markedly inhibited the reduction in cytokine secretion from lipopolysaccharide (LPS)-stimulated splenocytes. IFNγ-treated mice had significantly increased the percentages of positive costimulatory receptor CD86 on Dendritic cells expressing and expression of splenic HLA-DR. IFNγ markedly reduced DC-cell apoptosis by upregulating the expression of Bcl-2 and downregulating the expression of Bax. CLP-induced formation of regulatory T cells in the spleen was abolished in IFNγ -treated mice. IFNγ treatment reduced the expression of autophagosomes in DC cells. IFNγ significant reduce the expression of Warburg effector-related proteins PDH, LDH, Glut1, and Glut4, and promote glucose consumption, lactic acid, and intracellular ATP production. After the use of 2-DG to suppress the Warburg effect, the therapeutic effect of IFNγ was suppressed, demonstrating that IFNγ reverses immunosuppression by promoting the Warburg effect. Moreover, IFNγ increased the expression of phosphoinositide 3-kinases (PI3K), protein kinase B (Akt), rapamycin target protein (mTOR), hypoxia-inducible factor-1 (HIF-1α), pyruvate dehydrogenase kinase (PDK1) protein, the use of 2-DG and LY294002 can inhibit the expression of the above proteins, LY294002 also inhibits the therapeutic effect of IFNγ.
It was finally proved that IFNγ promoted the Warburg effect through the PI3K/Akt/mTOR pathway to reverse the immunosuppression caused by sepsis. This study elucidates the potential mechanism of the immunotherapeutic effect of IFNγ in sepsis, providing a new target for the treatment of sepsis.
Chiral ferroelectric crystals with intriguing features have attracted great interest and many with point or axial chirality based on the stereocarbon have been successively developed in recent years. ...However, ferroelectric crystals with stereogenic heteroatomic chirality have never been documented so far. Here, we discover and report a pair of enantiomeric stereogenic sulfur‐chiral single‐component organic ferroelectric crystals, Rs‐tert‐butanesulfinamide (Rs‐tBuSA) and Ss‐tert‐butanesulfinamide (Ss‐tBuSA) through the deep understanding of the chemical design of molecular ferroelectric crystals. Both enantiomers adopt chiral‐polar point group 2 (C2) and exhibit mirror‐image relationships. They undergo high‐temperature 432F2‐type plastic ferroelectric phase transition around 348 K. The ferroelectricity has been well confirmed by ferroelectric hysteresis loops and domains. Polarized light microscopy records the evolution of the ferroelastic domains, according with the fact that the 432F2‐type phase transition is both ferroelectric and ferroelastic. The very soft characteristics with low elastic modulus and hardness reveals their excellent mechanical flexibility. This finding indicates the first stereosulfur chiral molecular ferroelectric crystals, opening up new fertile ground for exploring molecular ferroelectric crystals with great application prospects.
Following the discovery of the first ferroelectric chiral Rochelle salt more than 100 years ago, the first pair of stereogenic heteroatom sulfur‐chiral ferroelectric crystals is reported on this study. The findings provide a perspective for the development of heteroatomic chiral ferroelectric crystals with great application prospects.
•DCNNs were used for regression and classification predictions of soil properties.•DCNNs outperformed single-task shallow CNN and traditional approaches.•DCNNs do not need spectral dimension ...reduction for modeling soil spectral data.•The position of feature wavelengths differed among the soil properties.
Soil, as a non-renewable resource, should be monitored continuously to prevent its degradation and promote sustainable agriculture. Soil spectroscopy in the visible-near infrared range is a fast and cost-effective analytical technique to predict soil properties. Although traditional machine learning methods are widely used for modeling soil spectral data, large spectral datasets may require better analytical methods for big data. Here, we explored the modeling potential of deep convolutional neural networks (DCNNs) for soil properties based on a large soil spectral library. The European topsoil dataset provided by the Land Use/Cover Area frame Survey (LUCAS) was used for DCNN modeling with the original absorbance spectra. Two single-task 16-layer DCNN models (LucasResNet-16 and LucasVGGNet-16) were used to make regression predictions of seven soil properties and classification predictions of soil texture. The effects of data pre-processing on single-task and multi-task DCNN modeling were assessed. The SHapley Additive exPlanations method was used to interpret the output of a DCNN model (LucasResNet-16). The DCNN models produced accurate predictions for most soil properties, and were superior to a single-task shallow convolutional neural network and traditional machine learning methods. Spectral transformation was effective for predicting some soil properties, while spectral downsampling led to a reduction in the modeling accuracy. The performance of a multi-task DCNN model built on the basis of LucasResNet-16 was improved compared with the performance of the single-task model. Soil organic carbon content, nitrogen content, cation exchange capacity, pH, and calcium carbonate content were well predicted, with the root mean squared error of 19.130 g∙kg−1, 0.971 g∙kg−1, 6.614 cmol(+)∙kg−1, 0.326, and 24.526 g∙kg−1, respectively. The overall classification accuracy of soil texture was 0.749 (four groups) and 0.566 (12 levels). The position of feature wavelengths differed among the soil properties, for which multiple characteristic peaks were common. This study fully demonstrates the modeling potential of deep learning with soil ultraspectral data, which could enhance precision agriculture.
The 3D lip synchronization is one of the hot topics and difficulties in the field of computer graphics. How to carry out 3D lip synchronization effectively and accurately is an important research ...direction in the field of multimedia. On this basis, a comprehensive weighted algorithm is introduced in this paper to sort out the related laws and the time of lip pronunciation in animation multimedia, carry out the vector weight analysis on the texts in the animation multimedia, and synthesize a matching evaluation model for 3D lip synchronization. At the same time, the goal of simultaneous evaluation can be achieved by synthesizing the transitional mouth pattern sequence between consecutive mouth patterns. The results of the simulation experiment indicate that the comprehensive weighted algorithm is effective and can support the evaluation and analysis of animation multimedia 3D lip synchronization.
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