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A penguin with bow tie-like bimetallic metal-organic framework, Cu3(MoO4)(TZ)2(OH)2 (Cu/Mo-MOF) {TZ = tetrazole}, was designed and fabricated by hydrothermal reaction of (NH4)6Mo7O24, Cu(NO3)2, NH4VO3 and 1H-tetrazole (HTZ). Single crystal X-ray diffraction shows the basic building unit of Cu/Mo-MOF is a “penguin shape” [6 + 6] metallocycles, which are further extended into a two-dimensional layer by “end-to-end” along the y-axis and an inverted “side by side” along the z-axis. It is interesting that the MoO42- anion looks like a bow tie that ties on the metallocycle improving structure stability. The bimetallic Cu/Mo-MOF was employed to detect H2O2 and L-Cys as a nanoenzyme; results from the peroxidase-like activity assay indicate the Cu/Mo-MOF possesses intrinsic peroxidase-like activity. Meanwhile, to enhance the sensor performance of Cu/Mo-MOF, the Cu/Mo-MOF/PPy nanocomposite was prepared by a chemical oxidation polymerization process of Py. Benefiting from the more active sites and the electrode/electrolyte interface, and the better electron diffusion and transport of Cu/Mo-MOF and PPy, the peroxidase-mimicking activity of the bimetallic Cu/Mo-MOF/PPy nanocomposite indeed can be greatly improved for the H2O2 and L-cysteine (L-Cys) detection, and the Cu/Mo-MOF/PPy nanocomposite exhibits a lower limit of detection (0.158 μM) among reported materials to date.

The adsorption and activation of gas molecules are investigated substantially in solid-gas heterogeneous catalysis. Here we investigated the interaction between gas molecules and unique two-dimensional monolayer Au (111) structure using density functional theory. It is found that CO2, H2O, N2 and CH4 molecules are weakly adsorbed on the surface with the adsorption energies between −0.150 and −0.250 eV due to van der Waals interaction. While CO, NO, NO2, and NH3 molecules are adsorbed more stably with the adsorption energies between −0.300 and −0.470 eV. Especially, the bond length of CO is stretched by 0.038 A and the bond angle of NO2 is obviously enlarged by 10.460°. The activation originates from the rearrangement of molecule orbitals and the orbitals hybridization between the partial orbitals of gas molecules and Au-5d orbitals. The fundamental analyses of adsorption mechanism and electronic properties may provide guidance for the applications of two-dimensional monolayer metal catalysis. PACSnumbers 73.22.-f, 73.61.-r

Perovskite-type transition metal oxides have emerged as promising electrocatalysts for various electrocatalytic reactions owing to their low cost, compositional tunability and high stability. However, insufficient electrocatalytic activities of pristine perovskite oxides hinder their pathway towards real-world applications. The incorporation of heteroatoms into perovskite oxide structures has been regarded as an efficient way to improve the electrocatalytic performance. This minireview summarizes the recent advances in the heteroatom doping of perovskite oxides as efficient electrocatalysts for the hydrogen evolution reaction (HER), oxygen evolution reaction (OER) and oxygen reduction reaction (ORR). These heteroatom doping strategies are classified based on various types of doping sites. The mechanisms of improved electrocatalytic activities are discussed in detail within different doping sites and various kinds of dopants. Finally, the remaining challenges and perspectives are outlined for future developments of perovskite oxide-based catalysts.

Perivascular adipose tissue (PVAT) homeostasis plays an important role in maintaining vascular function, and PVAT dysfunction may induce several pathophysiological situations. In this study, we investigated the effect and mechanism of the local angiotensin II (Ang II) on PVAT. High-throughput comparative proteomic analysis, based on TMT labeling combined with LC-MS/MS, were performed on an in vivo Ang II infusion mice model to obtain a comprehensive view of the protein ensembles associated with thoracic PVAT (tPVAT) dysfunction induced by Ang II. In total, 5037 proteins were confidently identified, of which 4984 proteins were quantified. Compared with the saline group, 145 proteins were upregulated and 146 proteins were downregulated during Ang II-induced tPVAT pathogenesis. Bioinformatics analyses revealed that the most enriched GO terms were annotated as gene silencing, monosaccharide binding, and extracellular matrix. In addition, some novel proteins, potentially associated with Ang II infusion, were identified, such as acyl-CoA carboxylase α, very long-chain acyl-CoA synthetase (ACSVL), uncoupling protein 1 (UCP1), perilipin, RAS protein-specific guanine nucleotide-releasing factor 2 (RasGRF2), and hypoxia inducible factor 1α (HIF-1α). Ang II could directly participate in the regulation of lipid metabolism, transportation, and adipocyte differentiation by affecting UCP1 and perilipin. Importantly, the key KEGG pathways were involved in fatty acid biosynthesis, FABP3-PPARα/γ, RasGRF2-ERK-HIF-1α, RasGRF2-PKC-HIF-1α, and STAT3-HIF-1α axis. The present study provided the most comprehensive proteome profile of mice tPVAT and some novel insights into Ang II-mediated tPVAT dysfunction and will be helpful for understanding the possible relationship between local RAS activation and PVAT dysfunction.

RhoGTPase is involved in PDGF-BB-mediated VSMC phenotypic modulation. RhoGDIs are key factors in regulating RhoGTPase activation. In the present study, we investigated the regulatory effect of RhoGDI1 on the activation of RhoGTPase in VSMC transformation and neointima formation. Western blot and co-immunoprecipitation assays showed that the PDGF receptor inhibition by crenolanib promoted RhoGDI1 polyubiquitination and degradation. Inhibition of RhoGDI1 degradation via MG132 reversed the decrease in VSMC phenotypic transformation. In addition, RhoGDI1 knockdown significantly inhibited VSMC phenotypic transformation and neointima formation in vitro and in vivo. These results suggest that PDGF-BB promotes RhoGDI1 stability via the PDGF receptor and induces the VSMC synthetic phenotype. The co-immunoprecipitation assay showed that PDGF-BB enhanced the interaction of RhoGDI1 with Cdc42 and promoted the activation of Cdc42, these enhancements were blocked by crenolanib and RhoGDI1 knockdown. Moreover, RhoGDI1 knockdown and crenolanib pretreatment prevented the localization of Cdc42 to the plasma membrane (PM) to activate and improve the accumulation of Cdc42 on endoplasmic reticulum (ER). Furthermore, Cdc42 inhibition or suppression significantly reduced VSMC phenotypic transformation and neointima formation in vitro and in vivo. This study revealed the novel mechanism by which RhoGDI1 stability promotes the RhoGDI1-Cdc42 interaction and Cdc42 activation, thereby affecting VSMC phenotypic transformation and neointima formation.

A series of carbon quantum dot (CQD)/Bi2WO6 hybrid materials were synthesized via a facile in situ hydrothermal method, where the CQDs were prepared using different carbon sources. As demonstrated by multiple techniques, including XRD, SEM, TEM, XPS, BET, UV-vis, FT-IR, PL and TPR, the visible light absorption wavelength red-shifted, the oxidation ability was enhanced, and the recombination probability of electron–hole pairs was inhibited by incorporating the CQDs in Bi2WO6. Moreover, different carbon source-derived CQD/Bi2WO6 materials exhibited different optical and electronic properties. The CQD/Bi2WO6 materials exhibited excellent activity in the photocatalytic degradation of VOCs under visible light irradiation, among which the CQDs/Bi2WO6 derived from chitosan demonstrated the best activity with 96.9% degradation for gaseous toluene and 97.1% for gaseous formaldehyde within only 120 min. Furthermore, the CQDs/Bi2WO6 showed high stability and reusability.

A new polyoxometalate-based coordination polymer, Ag2(L)2(VW12O40)][Ag2(L)2]·4H2O (1) {L = 3,5-di(1H-1,2,4-triazol-1-yl)benzoic acid}, has been isolated under hydrothermal conditions and characterized by routine methods. Compound 1 exhibits an interesting 1D + 1D polypseudo-rotaxane architecture, as shown by X-ray diffraction analysis. The new compound represents a scarce example of 1D + 1D polypseudo-rotaxane architecture, namely, ladder motifs are threaded by zigzag chains rather than a straight one. The coordination stability around loop and thread motifs was investigated to expatiate on the zigzag chained polypseudo-rotaxane. In addition, crystal 1 can be used as a packing material to selectively adsorb cationic dyes such as crystal violet (CV) and methylene blue (MB) concomitant with methyl orange anionic dyes with high uptakes and rapid adsorption rate.

Graphitic carbon nitride (g-C3N4), characterized with a suitable bandgap, has aroused great interest as a robust and efficient catalyst for solar energy utilization. Herein, we introduce a new strategy to fabricate a three-dimensional (3D) porous g-C3N4 by a facile NaCl-assisted ball-milling strategy. The porous structure-induced advantages, such as a higher specific surface area, more efficient charge separation, and faster electron-transfer efficiency, enable the 3D porous g-C3N4 to achieve impressive properties as a bifunctional catalyst for both photocatalytic hydrogen evolution and electrocatalytic oxygen evolution reaction (OER). As a result, the 3D porous g-C3N4 exhibits a hydrogen evolution rate of 598 μmol h-1 g-1 with an apparent quantum yield of 3.31% at 420 nm for photocatalytic H2 generation, which is much higher than that of the bulk g-C3N4. Simultaneously, the porous g-C3N4 also presents an attractive OER performance with a low onset potential of 1.47 V (vs reversible hydrogen electrode) in an alkaline electrolyte after rational cobalt-doping. Accordingly, the NaCl-assisted ball-milling strategy paves the way to the rational design of a controllable porous structure.

Due to the redox properties closely related to numerous physiological and pathological processes, biothiols, including cysteine (Cys), homocysteine (Hcy) and glutathione (GSH), have received considerable attention in biological science. On account of the important physiological roles of these biothiols, it is of profound significance to develop sensitive and selective detection of biothiols to understand their biological profiles. In this work, we reported an efficient fluorescent probe, PHPQ-SH, for detecting biothiols in vitro and vivo, based on the phenothiazine-HPQ skeleton, with DNBS (2,4-dinitrobenzenesulfonate) as the response unit. Probe PHPQ-SH exhibited brilliant sensing performances toward thiols, including a large Stokes shift (138 nm), excellent sensitivity (for GSH, LOD = 18.3 nM), remarkable fluorescence enhancement (163-fold), low cytotoxicity, rapid response (8 min), and extraordinary selectivity. Finally, the probe PHPQ-SH illustrated herein was capable of responding and visualizing biothiols in MCF-7 cells and zebrafish.

Transarterial radioembolization (TARE) is considered the standard treatment for intermediate-stage hepatocellular carcinoma (HCC). Iodine-131 (131I)-labeled lipiodol TARE is an effective treatment for HCC but has been withdrawn due to its poor retention in tumor lesions and significant distribution in normal tissues with severe side effects. In this work, a highly tumor-specific 131I-TARE agent with long-time retention is developed by simply introducing tyrosine to poly(vinyl alcohol) (PVA) drug-eluting microbeads (Tyr-PVA-DEBs). The labeling efficiency of 131I-labeled microbeads remains above 85% in 50% serum for 31 days. Micro-single-photon emission computed tomography/computed tomography (μSPECT/CT) evidences that the 131I-labeled microbeads accumulate in the orthotopic N1S1 hepatoma of rats for 31 days following intra-arterial injection. The cumulative radiation dose per cubic centimeter of the tumor is at least 13 678-fold higher than that of normal tissues. The highly tumor-selective radiation of the 131I-labeled microbeads allows localized delivery of 345.04 ± 139.16 Gy to the tumor following a single injection dose as low as 0.2 mCi of 131I. Moreover, the 131I-labeled microbeads are loaded with doxorubicin hydrochloride (DOX) through the carboxy groups on tyrosine of the polymer. The 131I-DOX-loaded microbeads present a synergetic antitumor effect without recurrence in comparison with the microbeads labeled with 131I or loading DOX alone, attributed to the sensitization of DOX to 131I-induced ionizing radiation damage to DNA under the embolization-induced hypoxia. Our results demonstrate a high tumor retention of 131I-labeled embolic agent for low-dose transarterial radio-chemoembolization (TARCE) with a synergetic therapeutic effect on treating HCC, showing potential for clinical application.

Highlights The multiple thermal treatments strategy is proposed for preparing the hollow oxygen-incorporated g-C3N4 nanosheets (OCN).Oxygen-adsorption creates a lot of defects to the formation of hollow and monolayered structure, while oxygen-doping reduces the band gap significantly.OCN exhibits stable and high photocatalytic hydrogen evolution with increased surface area, enhanced charge transport, and reduced band gap. Supporting information The online version of this article (10.1007/s40820-020-00571-6) contains supplementary material, which is available to authorized users., Graphitic carbon nitride (g-C3N4)-based photocatalysts have shown great potential in the splitting of water. However, the intrinsic drawbacks of g-C3N4, such as low surface area, poor diffusion, and charge separation efficiency, remain as the bottleneck to achieve highly efficient hydrogen evolution. Here, a hollow oxygen-incorporated g-C3N4 nanosheet (OCN) with an improved surface area of 148.5 m2 g−1 is fabricated by the multiple thermal treatments under the N2/O2 atmosphere, wherein the C–O bonds are formed through two ways of physical adsorption and doping. The physical characterization and theoretical calculation indicate that the O-adsorption can promote the generation of defects, leading to the formation of hollow morphology, while the O-doping results in reduced band gap of g-C3N4. The optimized OCN shows an excellent photocatalytic hydrogen evolution activity of 3519.6 μmol g−1 h−1 for ~ 20 h, which is over four times higher than that of g-C3N4 (850.1 μmol g−1 h−1) and outperforms most of the reported g-C3N4 catalysts. Supporting information The online version of this article (10.1007/s40820-020-00571-6) contains supplementary material, which is available to authorized users.

Carbon nitride has drawn widespread attention as a low-cost alternative to metal-based materials in the field of photocatalysis. However, the traditionally synthesized carbon nitrides always suffer a bulky architecture, which limits their intrinsic activities. Here, a cycloaddition reaction is proposed to synthesize a triazine-based precursor with implanted sodium and cyano groups, which are mostly retained in the resulting carbon nitride after the following polymerization. Incorporated sodium and cyano defects can not only tune the band structure of the carbon nitride but also provide more additive active sites. The optimized properties enable it an adorable photocatalytic hydrogen evolution rate of 1070 μmol h-1 g-1, varying by almost an order of magnitude from the pristine carbon nitride (79 μmol h-1 g-1). Moreover, a sequential self-assembly strategy has been adopted to further improve its architecture. As a consequence, a three-dimensional (3D) porous carbon nitride microtube cluster is constructed, indicating abundant exposed active sites and the faster separation of charge carriers. The corresponding photocatalytic hydrogen evolution rate is 1681 μmol h-1 g-1, which is very competitive compared with the reported pure carbon nitride photocatalysts. Briefly, this new approach may offer opportunities to fabricate task-specific carbon- and nitrogen-based materials from the molecular level.

Background: In this study, we investigated the mechanism of Rho GTPases signaling on Ang II-mediated cell migration and dedifferentiation in human aortic vascular smooth muscle cells (HA-VSMCs) and an Ang II-infusion mouse model. Methods: Cells were pretreated with different inhibitors or Ang II. Cell migration was detected by Wound healing and Transwell assay. Mice were treated with Ad-RhoA-shRNA virus or Irbesartan or fasudil and then infused with Ang II. Results: Ang II treatment induced HA-VSMCs migration in a dose- and time-dependent manner and reduced the expression of VSMC contractile proteins. These effects were significantly suppressed by the inhibition of Ang II type 1 receptor (AT1 receptor), RhoA, and Rho-associated kinase (ROCK). Furthermore, Ang II treatment promoted the activation of RhoA and ROCK, which was reduced by AT1 receptor inhibition. Meanwhile, Ang II treatment induced F-actin polymerization, which was inhibited after ROCK inhibition. In mice, Ang II infusion increased VSMC migration into the neointima and reduced VSMC differentiation proteins levels, and these effects were shown to be dependent on AT1 receptor and RhoA/ROCK pathway. Conclusion: This study reveals a novel mechanism by which Ang II regulates RhoA/ROCK signaling and actin polymerization via AT1 receptor and then affects VSMC dedifferentiation.

Background: Bone marrow mesenchymal stem cells can promote the recovery of immune balance and regulate the balance of Th1/2 cells. Allergic rhinitis is a disease with Th1/2 imbalance mediated by IgE. It’s unclear whether BMSCs could regulate AR disease. In this study, the possible role of BMSCs was explored. Methods : AR mouse model was established by ovalbumin (OVA). 18 models were randomly divided into three groups: AR-sensitized, Stem-cell-returned, Medium-returned; six unsensitized mouses named normal-control. IgE, IL-4 and INF-γ levels were measured by Elisa. Observing migration of BMSCs by immunofluorescence. Flow cytometry used to detect changes of Th1/2. STAT 4/6 protein level was detected by Western-blot. Results : After OVA-sensitization, IgE, IL-4 and STAT6 levels were higher, INF-γ and STAT4 level was lower. Flow cytometry revealed a decrease in Th1 cell and an increase in Th2 cell in AR group. After BMSCs treatment, t IgE, IL-4 and STAT6 levels in SCRg and MRg were lower than that in AR group, and tINF-γ and STAT4 level were higher than hat inAR group. Flow cytometry showed that the content of Th1 cell increased while Th2 cell decreased. Conclusions: BMSCs return treatment could decrease the expression of IL-4, promote the expression of INF-γ and regulate the balance of Th cell, and the mechanism was closely related to STAT4/6 signaling pathway. However there was no statistical difference between SCRg and MRg, so the role of BMSCs maybe achieved through paracrine function rather than multi-directional differentiation potential.

A new 12-tungstovanadate-templated 3D nanocage framework, Ag10(μ4-ttz)4(H2O)4(VW12O40) (VW12@MOCF), was designed based on a “molecular library”, hydrothermally synthesized, structurally characteriz...

Two-dimensional (2D) heterostructures have emerged as promising electrocatalysts towards oxygen evolution reaction due to their unique structural and chemical properties. Moreover, 2D lateral heterostructure with the coupled interface in-plane rather than the vertical direction enables to expose more active sites to catalyst surface, and thus facilitates the OER catalytic activity. Here, 2D FeCo layered double hydroxide/cobalt oxide (FeCo LDH/CoO) nanosheets are synthesized via an instantaneous method utilizing molten alkali as both solvent and reactant. Upon a selective low-temperature phosphorization, 2D Fe-containing cobalt phosphide/cobalt oxide (Fe-CoP/CoO) lateral heterostructure with the optimized electronic structure and activated electronic coupling interface is obtained and exhibits superior catalytic activity (η = 219 mV at 10 mA cm−2) compared to most of the reported electrocatalysts towards OER in alkaline electrolyte. Besides, both of the experimental characterization and DFT calculation are performed to illustrate the detailed mechanism of the attractive OER activity. It is uncovered that the coupled interface between CoP and CoO induces the redistribution of electrons, facilitates the adsorption of OH- anions easily, and thus optimizes Gibbs free energies for water oxidation.

If fertilization does not occur for a prolonged period in vivo or in vitro, the postovulatory oocytes will deteriorate, which called the postovulatory aging. This process disrupts the developmental competence. In the present study, we showed that the reactive oxygen species (ROS) was accumulated in oocytes during the postovulatory aging. ROS inhibited Sirt1 expression, and then increased oxidative stress by downregulating the intracellular Sirt1-FOXO3a-SOD2 axis. Moreover, the inhibited Sirt1 expression was related to the decreased mitochondrial function and the lowered level of autophagy. The mitochondrial-related apoptosis was increased by inhibiting the AKT and ERK1/2 pathways, due to the accumulation of ROS in the postovulatory oocytes. The mitochondrial pyruvate dehydrogenase kinase-4 (PDK4) can reduce ROS by inhibiting the tricarboxylic acid (TAC) cycle. We found that PDK4 was significantly decreased in the postovulatory aging oocytes. Putrescine, one of the abundant biogenic amines, ameliorated the effects of ROS and therefore improved the quality of the postovulatory aging oocytes by increasing the expression of PDK4. When PDK4 was downregulated using siRNAs, the effects of putrescine were significantly receded. We concluded that putrescine delayed the aging process of postovulatory oocytes by upregulating PDK4 expression and improving mitochondrial activity.

Development of efficient electrocatalysts for overall water splitting is an attractive and challenging task. Here, we present a simple one-step electrodeposition for the synthesis of ferroferric oxide (Fe3O4) decorated cobalt monophosphide (CoPx) nanoflowers formed on titanium nitride (TiN) nanoarrays. Accompanied with the TiN nanoarrays as a support, the synthesized Fe3O4–CoPx/TiN exhibits an excellent activity with an onset potential of 50 mV as well as superior stability even after 100 h for hydrogen evolution reaction (HER). Besides, the Fe3O4–CoPx/TiN composite delivers a current density of 10 mA cm–2 at a low overpotential of 331 mV for oxygen evolution reaction (OER), which outperforms the Ir-based noble-metal catalysts. Remarkable activities for HER and OER are ascribed to the synergetic effects among each component and the reinforced structural stability. Specifically, the incorporation of Fe3O4 into phosphide promotes the electron donor–acceptor properties during the catalytic progress that lead...

A new POM-templated metal-organic framework [Ag8L4][PMo12O40]·OH {HL = 5-[4-(1,2,4-triazol-4-yl)phenyl]-1H-tetrazole} containing metal-organic nanocage and left- and right-handed helixes has been isolated under hydrothermal conditions. The Keggin POM plays a template role in the formation of macrocycle and metal-organic nanocage, as shown by X-ray diffraction analysis. The new compound represents a scarce example of POM-encapsulated metal-organic nanocage. Additionally, its photocatalytic degradation of RhB was also investigated.

2D metal coordination polymers have emerged as a new serious of efficient electrocatalysts in OER for their abundant unsaturated coordination centers and high charge-carrier mobility. However, the synthetic routes are mostly depending on the top-down exfoliation with unavoidable structural fragmentation and the annoying sheets’ re-stacking. Here, an electrocatalytic poly (triazine imide) ligand is firstly synthesized and successfully applied to construct the 2D Ni/Fe coordination polymers nanosheets (Ni/Fe-CPNs) through a bottom-up strategy. Average thickness of the nanosheets is around 5 nm, enabling the highly exposed reactive centers. Further benefiting from the ligand promotion effect, absorption of the oxygen species during the OER is effectively accelerated, thus improving the reaction kinetics. Accordingly, the Ni/Fe-CPNs reveals an adorable overpotential of 244 mV at the current density of 10 mA cm−2, and the Tafel value of 65.8 mv dec−1. Both values are much better than that of commercial RuO2, and competitive to most of the reported catalysts. The ex-situ techniques, including Raman, FT-IR and XPS analysis alongside with applied potential, are also applied to elaborate the catalytic mechanism. This work offers a new point of view to improve the catalysts’ activity.

Ingenious design of catalysts structure is vital for accelerating ammonium perchlorate (AP) thermal decomposition at lower temperature and accompanying with more heat release. In this work, a self-templated approach is adopted to construct hierarchical hollow double-shelled Co3O4 using cobalt glycerate solid spheres as precursors. The structural transformation from the solid species to the hollow double-shelled Co3O4 sphere is implemented by a solution growth combined with a subsequent calcination. The hierarchical hollow double-shelled morphology, large surface area and unique electronic structure endue Co3O4 with enhanced catalytic performance for thermal decomposition of AP. The AP decomposition temperature is decreased to 318 °C and heat release is increased from 491 J g−1 to 1280 J g−1.

Designing a highly efficient and low-cost electrocatalyst for hydrogen evolution reaction (HER) is of great importance to produce high-purity hydrogen, yet it still remains a huge challenge. Here, we present a facile synthesis of this electrocatalyst, PtRu alloy nanoparticles supported on C2N nanosheets, using a condensation-reduction approach. The PtRu@C2N exhibits comparable performance than the commercial Pt/C and higher efficiency than monometallic Pt@C2N and Ru@C2N in both acidic and alkaline conditions. The highly enhanced activity and fast kinetics of PtRu@C2N were attributed to the large electrochemical active surface area, unique electronic structure of PtRu nanoparticles on C2N nanosheets. Density functional theory calculations show that the alloy effect and the metal-support interaction in PtRu@C2N catalyst optimizes the adsorption energy of H atom and other intermediates, resulting in the improvement of HER activity.

The objective of this study was to determine the effects of rice residue on the physicochemical properties of silver carp surimi gels. The whiteness of gels was slightly decreased when rice residue was added. Breaking force and deformation of gels were significantly decreased with more than 1% rice residue addition (p

Electrochemical nitrogen reduction reaction (NRR) is becoming increasingly promising alternatively to the traditional Haber-Bosch process but developing efficient electrocatalysts is still a challenge. In this job, we searched that the catalytic performance of Cr2B2 for NRR by way of density functional theory (DFT) calculations. We mainly screened out four favorable N2 adsorbed structures, including N2 adsorption on the B-B bonds, Cr-B bonds, top site of B and Cr atom. It was found that the largest adsorption energy was −1.235 eV when N2 was adsorbed on the Cr-B bond in a side-on structure, and has a better excellent NRR catalytic activity with the limiting potential is 0.29 V. The catalytic activity of all structures was better in the alternating mechanism of nitrogen reduction reaction. As the antibonding orbitals approach the Fermi level, the number of electrons in the antibonding orbitals increases. The limiting potential of TCr_end can also be reduced from 0.88 V to 0.35 V by N N bond breaking after the second hydrogen, which contribute to the greater NRR performance. We hope that this research will offer a viable strategy for the design of NRR catalysts, and offer a new way of thinking for MBene as a catalyst for NRR.

Microbial denitrification in agriculture makes a considerable contribution to terrestrial nitrous oxide (N 2 O) emissions, and the prevailing view is that this mainly occurs in soil. Here, we show the root N 2 O emission capacity of wheat grown under three long-term (32-year) fertilization regimes, and compare root-, rhizosphere- and soil-inhabiting denitrifying microbial communities. The N 2 O/(N 2 O + N 2 ) product ratio of denitrification in the root was 0.5–9.2-fold higher than that in surrounding soil under fertilized conditions, especially manure application. Root N 2 O/(N 2 O + N 2 ) ratio was closely related to the proportion of two nitrite-reductase genes ( nirK / nirS ), with higher N 2 O emission associated with increased nirS abundance. Rhodobacterales and Pseudomonadales dominated the root-associated nirS community. In contrast, soils showed a higher proportion of unclassified denitrifiers. Our results demonstrate the potential of wheat to emit N 2 O from the roots that harbour low-complexity denitrifying communities distinct from those occurred in soils.

Carbon nitride has attracted significant interest as robust, low-cost alternative to metal-based materials in fields such as photo, electro and heterogeneous catalysis. However, the properties of the final material are hard to control by traditional synthetic methods Herein, we introduce a new strategy of material design that allows controlling the desired properties of the final material already from the molecular level by sequential solvent treatment of supramolecular aggregates that serve as the reactants. Due to in situ formation of a thermodynamic driven energy levels gradient, the as-prepared carbon nitride exhibits almost 10 times higher activity than the traditional carbon nitride (calcined from melamine) in the hydrogen evolution text. As a multifunctional catalyst, the core-shell like carbon nitride also shows a superior catalytic degradation activity for RhB and p -nitrophenol.

A new cyan fluorescent probe, MIPY-DNBS, using an imidazo[1,5-&alpha, ]pyridine derivative as the fluorophore and 2,4-dinitrobenzensufonate as the recognition site for the selective detection of thiols (Cys, GSH, and Hcy), was designed and synthesized. Probe MIPY-DNBS exhibited a 172 nm Stokes shift, a fast response time (400 s), low cytotoxicity, low detection limits (12.7 nM for Cys), and excellent selectively in the detection of thiols. In addition, MIPY-DNBS was successfully applied to imaging thiols in living MCF-7 cells and zebrafish.

By modifying the 10-butyl-2-methoxy-10H-phenothiazine-3-carbaldehyde with malonontrile group, a new fluorescent sensor PBM for selective detection of hydrazine in ratiometric mode has been developed. Probe PBM owned the advantages of quick response (10 min), remarkable Stokes shift (168 nm for PBM, 161 nm for PBM-NH2), excellent selectivity, high sensitivity (detection limit of 63.2 nM was obtained from in vitro experiment), profound ratiometric change (82-fold) and low cytotoxicity in response to hydrazine. Additionally, it could be utilized to monitor hydrazine in gas state with various concentrations through vivid color changes and imaged hydrazine in living MCF-7 cells with excellent performance.

By taking advantage of the intramolecular charge transfer (ICT) process, we presented a novel fluorescent probe IPY-SO2 based on imidazo[1,5-α]pyridine derivative for detecting SO32− with a low detection limit (70 nM). Combining its favorable turn-on fluorescence feature (75-fold), rapid response (5 min), high selectivity, large Stokes shift (174 nm) and low cytotoxicity, IPY-SO2 was successfully applied to imaging SO32 in living MCF-7 cells and zebrafish.

Metallic gold (Au) nanoparticles have great potential for a wide variety of biomedical applications. Yet, slow clearance of Au nanoparticles significantly hinders their clinical translation. Herein, we describe a strategy of utilizing the endogenous copper (Cu) clearance to improve the elimination of Au nanoparticles. Our mechanistic study reveals that a Cu-transporting P-type ATPase, ATP7B, mediates the exocytosis of CuS nanoparticles into bile canaliculi for their rapid hepatobiliary excretion. The efflux of CuS nanoparticles is adopted to facilitate the hepatobiliary clearance of Au nanoparticles through CuS-Au conjugation. Using two different CuS-Au nanoconjugates, we demonstrate that CuS increases the biliary Au excretion of CuS-Au nanospheres or CuS-Au nanorods in mice or rats in comparison to that of their respective unconjugated Au nanoparticles postintravenous injection. The current CuS-Au conjugation approach provides a feasible strategy to enhance the hepatobiliary clearance of Au nanoparticles that may be applicable to various structures.

Hypochlorite (ClO−), as a typical weak acidic ROS, is mainly endogenously produced by myeloperoxidase (MPO) catalyzing hydrogen peroxide (H2O2) and chloride ion (Cl−) in leukocytes. Imbalance of hypochlorite concentration will not only cause biomolecular oxidation in organism, but also are correlated with a variety of physiological diseases. In this study, a novel ratiometric fluorescence probe PHPQ for detecting ClO- by incorporating the phenothiazine moiety into the HPQ fluorophore was designed and synthesized. The probe PHPQ was shown to be capable of selectively and sensitively monitoring ClO- in a fine ratiometric manner. It also displayed the merits of large blue-shift (98 nm), rapid response (30 s), excellent sensitivity (15 nM) and significant fluorescence ratiometric variations (253-fold). Moreover, PHPQ was successfully utilized for bioimaging exogenous/endogenous ClO- in living cells (MGC-803 and RAW264.7) and in zebrafish.

The combined application of organic materials and chemical fertilizers is an effective approach for improving crop productivity and soil quality. Purple soil is characterized by low N, P, and organic C contents that influence crop productivity. However, the optimal organic materials that can be used to improve purple soil quality and crop yields remain to be clarified. Here, we conducted a 13-year field experiment (from 2007 to 2019) in Sichuan Province, China, intending to assess the long-term influence of various combinations of organic materials and chemical fertilizers on soil enzymatic activities, microbial communities, and crop yields. Treatments included chemical fertilizer alone (NPK), NPK plus returned straw (NPKS), NPK plus pig manure (NPKM), NPK plus fungal residue (NPKF), and NPK plus green manure (Vicia villosa Rothvar.) (NPKG). Results showed that NPKM and NPKF treatments significantly increased the average yields of maize (7.9 and 6.4%, respectively) and wheat (15.7 and 12.9%, respectively) relative to NPK treatment. The highest sustainable yield index value of maize and wheat was observed in NPKF treatment. The long-term application of fungal residue (NPKF) significantly increased soil organic C and available P contents, relative to NPK、NPKS and NPKG treatments, and soil organic C content increased from 6.95 to 9.12 ± 1.06 g kg−1 and available P content from 6.87 to 12.26 ± 2.23 mg kg−1. Relative to NPK treatment, NPKF treatment significantly enhanced soil microbial biomasses (C, N, and P) and soil C-, N- and P-cycling enzyme activities but significantly decreased soil pH. The soil enzyme index following NPKF treatment was significantly higher relative to other treatments and was 208.6% higher than NPK treatment. Additionally, relative to NPK treatment, NPKF treatment altered soil microbial community structure, and significantly increased the rate of G+/G− and cy19/18:1ω7c. Soil microbial biomasses N, Nitrate N, and available P were the main factors regulating the change of microbial community in purple soil. We, therefore, conclude that NPKF treatment is an effective fertilization strategy for improving purple soil quality and crop yields.

Designing novel electrode materials with controlled structure and composition remains a great challenge for high-performance supercapacitors. Here, a triple-shelled hollow nanostructure has been successfully designed and constructed by confining amorphous Ni-Co-S/crystalline MnS on the inner walls and the outer surfaces of hollow carbon nanospheres. The triple-shelled hollow nanostructure can improve the electrochemically active surface areas, accelerate the transport of electrons/ions, and accommodate the volume change during cycling. Additionally, the interlayer (the porous hollow carbon nanospheres) can support each other for enhanced mechanical stability and improve the electrical conductivity of the electrode. More importantly, amorphous Ni-Co-S facilitates diffusion and redox reaction of OH–, while the crystalline MnS offers fast electrons transport and mechanical stability. Meanwhile, the amorphous/crystalline interface can improve charge storage. Benefiting from the structural and compositional advantages, the prepared electrode delivers a high specific capacity (1093C g−1 at 1 A g−1) and outstanding cyclic stability (capacity retention ratio of 90.4% at 10 A g−1 after 5000 cycles). The corresponding all-solid-state hybrid supercapacitor achieves long cycle life and high energy density.

As an abundant marine xanthophyll, fucoxanthin (FX) exhibits a broad range of biological activities. The preparation of high-purity FX is in great demand, however, most of the available methods require organic solvents which cannot meet the green chemistry standard. In the present study, a simple and efficient purification approach for the purification of FX from the brown seaweed Sargassum horneri was carried out. The FX-rich ethanol extract was isolated by octadecylsilyl (ODS) column chromatography using ethanol–water solvent as a gradient eluent. The overwhelming majority of FX was successfully eluted by the ethanol–water mixture (9:1, v/v), with a recovery rate of 95.36%. A parametric study was performed to optimize the aqueous ethanol precipitation process by investigating the effects on the purity and recovery of FX. Under the optimal conditions, the purity of FX was 91.07%, and the recovery rate was 74.98%. Collectively, the eco-friendly method was cost-efficient for the purification of FX. The developed method provides a potential approach for the large-scale production of fucoxanthin from the brown seaweed Sargassum horneri.

A new coordination polymeric chains modified polyoxometalate, H3K2[Ag5(DTB)5][SiW12O40]2·Cl2·8H2O (1) {DTB ​= ​1,4-di(1H-1,2,4-triazol-1-yl)benzene}, has been successfully synthesized under hydrothermal conditions. Single crystal X-ray diffraction analyses reveal that the Keggin POM cluster is modified by {Ag(DTB)}n chains in an unusually [2 ​+ ​4] asymmetrical mode resulting in a 2D double layer structure. By connection of K cations and π···π interactions between adjacent {Ag(DTB)}n coordination polymeric chains, the 2D structure extends to a 3D structure. In addition, crystal 1 can be used as a packing material for the highly selective adsorption and separation cationic dyes such as methylene blue (MB) and crystal violet (CV) against with methyl orange (MO) anionic dyes. The adsorption of a series of cationic organic dyes experiment demonstrated that this process is highly related to the sizes of organic dyes.

Although the hollow nanostructures as supercapacitor electrodes possess great advantages, the huge interior void seriously hindered the enhancement of volumetric power and energy densities. In this work, a hierarchical spherical nanostructure has been successfully designed and constructed by confining Ni–Co–Mn hydroxide nanosheets inside/outside hollow carbon nanospheres. The hollow carbon nanospheres show unique spatial confinement effect and surface-confined effect, which can well control the size of the Ni–Co–Mn hydroxide nanosheets about 340 nm encapsulated inside hollow carbon nanospheres as well as the thickness of Ni–Co–Mn hydroxide nanosheets (~13 nm) wrapped outside hollow carbon nanospheres. This ingenious hierarchical spherical nanostructure significantly enhanced the electrical conductivity and structural stability of Ni–Co–Mn hydroxide nanosheets as well as the packing density of electrode materials. Benefiting from the structural and compositional features, the as-obtained electrode achieves a high volumetric capacity (1455.2 C cm−3), favorable rate performance, and long cycle life. Impressively, the assembled hybrid supercapacitor device shows a high specific energy of 44.9 Wh kg−1 at the 793.5 W kg−1 and a high capacitance retention ratio of 91.8% after 10,000 cycles.

Heterogeneous materials with scientific design have drawn widespread attention for their morphology-dependent properties and synergistic effects in the application of volatile organic compound (VOC) sensing. Here, we report a sequential nucleation strategy to prepare a Co3O4-ZnO/reduced graphene oxide (rGO) heterogeneous composite via the electrostatic adsorption process, chemical coordination step and crystal nucleation procedure. In this approach, the volatility and alkalescence of ammonia effectively avoids spontaneous diffusion and exchange reactions among metal ions with similar radii. Benefitting from the stepwise pathways, the post-generated ZnO exhibits oriented growth along the 2 1 ¯ 1 ¯ 0 > face and a hexagonal morphology, which favors the VOC sensing. Based on this, the synthesized Co3O4-ZnO/rGO ternary composite shows an enhanced response (Ra/Rg) of 3.0 and a faster response/recovery of 19/12 s towards 5 ppm benzaldehyde in the gas phase than the individual and binary ZnO-based systems. Furthermore, it also presents a comparable sensitivity of 7.98 μAcm−2 mM−1 towards benzaldehyde in the liquid phase. These superior sensing abilities of the Co3O4-ZnO/rGO sensor can be attributed to the enhanced oxygen adsorption capacity by the large sensing area of hexagonal ZnO disk, the p-n effects of Co3O4-ZnO on rGO sheets, as well as the excellent characteristics of rGO sheets.

Here we report a facile synthesis of carbon nitride-based hydrogels with adjustable shapes, ranging from cylinder to tube and thin sheet, by photopolymerization process in confined templates. The fabricated hydrogel shows enhanced mechanical properties compared to the reference gel without carbon nitride incorporation, good adsorption capacity, and promising photocatalytic activity toward hydrogen production. Meanwhile, the hydrogel also exhibits selective pollutants adsorption properties that could be attributed to the negative-charged carbon nitride as well as relatively high stability alongside enhanced light harvesting. The novel carbon nitride-based hydrogels offer a facile approach as photocatalyst and open up many opportunities for smart-catalyst design with adjustable reaction sites.

Acid rain can directly or indirectly affect plant physiological functions, especially photosynthesis. The enzyme ATP synthase is the key in photosynthetic energy conversion, and thus, it affects plant photosynthesis. To clarify the mechanism by which acid rain affects photosynthesis, we studied the effects of acid rain on plant growth, photosynthesis, chloroplast ATP synthase activity and gene expression, chloroplast ultrastructure, intracellular H(+) level, and water content of rice seedlings. Acid rain at pH 4.5 remained the chloroplast structure unchanged but increased the expression of six chloroplast ATP synthase subunits, promoted chloroplast ATP synthase activity, and increased photosynthesis and plant growth. Acid rain at pH 4.0 or less decreased leaf water content, destroyed chloroplast structure, inhibited the expression of six chloroplast ATP synthase subunits, decreased chloroplast ATP synthase activity, and reduced photosynthesis and plant growth. In conclusion, acid rain affected the chloroplast ultrastructure, chloroplast ATPase transcription and activity, and P n by changing the acidity in the cells, and thus influencing the plant growth and development. Finally, the effects of simulated acid rain on the test indices were found to be dose-dependent.

By using BPMOH as the fluorophore and 2, 4-dinitrobenzenesulfonate moiety as the recognition site for thiols, a new long-wavelength emission (645 nm) fluorescent probe BPMSH with large Stokes shift (133 nm) was designed and synthesized. Probe BPMSH exhibited almost no fluorescence emission because of the PET process. When adding thiols, BPMSH could be quickly converted into BPMOH emitting a significant red fluorescence at 645 nm. In addition, BPMSH displayed high selectivity toward thiols among various biologically related analytes. Probe BPMSH has been applied to exogenous and endogenous thiols detection and imaging in living MCF-7 cells and MGC-803 cells. Most importantly, this probe BPMSH was successfully utilized for imaging thiols in zebrafish.

Sodium ion hybrid capacitors (SIHCs) have attracted considerable attentions due to their high-energy density of batteries and high-power output of supercapacitors. However, the slow intercalation kinetics of anode and low specific capacity of cathode greatly hinder the high-performance output of the SIHCs. Herein, we develop a facile chemical gas expansion method with chemical etching to prepare 3D nitrogen and sulfur co-doped porous carbon nanosheet (PCNS). As an anode material of SIBs, the PCNS displays a high reversible capacity of 205 mAh g−1 at 0.5 A g−1, outstanding rate capability of 96 mAh g−1 at 20 A g−1, and excellent cycle performance of 180 mAh g−1 at 7 A g−1 after 10 000 cycles. Based on this good performance, a dual-carbon SIHC is assembled by battery-type anode material (PCNS) and capacitive-type cathode material (hierarchically porous carbon). This device exhibits high energy densities of 119 Wh kg−1 and 53 Wh kg−1 at power densities of 200 W kg−1 and 20 kW kg−1, respectively. Besides, it possesses a superior cycle life of 82% capacity retention after 8000 cycles. Moreover, this work provides a new idea for the synthesis of carbon materials as high-performance SIBs and SIHCs electrode materials.

Bilayer phosphorene homojunctions have attracted considerable interest owing to their natural bandgap and high carrier mobility. However, very little is known about the valuableness in arrays of bilayer phosphorene homojunctions with different rotated angles. In this work, we have presented angular modulated electronic and optical properties of rotated bilayer phosphorene employing first-principles calculations based on density functional theory. The angles in the homojunctions of the rotated bilayer phosphorene are set to be 26.02 ° , 71.61 ° , 110.54 ° , 130.39 °, and 149.01 °, respectively, and the homojunctions demonstrate different bandgaps of 0.66 eV, 0.64 eV, 0.63 eV, 0.68 eV, and 0.67 eV, respectively, implying that these homojunctions are good candidates for application in optoelectronics and nanoelectronics. Interestingly, we found that the rotated bilayer phosphorene can greatly enhance the absorption of visible and infrared light, which would provide encouragement on the modeling of the rotated bilayer phosphorene in nanoelectronic and optoelectronic devices.

A new and simple synthetic route is introduced to covalently functionalize the carbon nitride (CN) framework by the implementation of halogenated phenyl groups (Cl, Br and I), which serve as a chemically reactive center, within the CN framework. The covalent modification is demonstrated here by substituting phenyl and tert-butyl propionate onto the modified-CN framework through Suzuki and reductive-Heck cross-coupling reactions, respectively. The effective functionalization leads to a facile exfoliation of the CN framework into thinner layers and greatly enhances the dispersibility in many solvents as well as the photocatalytic activity compared to the unmodified CN. The general covalent modification opens the possibility for tailor-made design of dispersible CN materials, including their photophysical and chemical properties, toward their exploitation in many fields, such as photocatalysis, bio-imaging, sensing, and heterogeneous catalysis.