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Chlorinated organic pollutants are highly toxic and widespread in the environment, which cause ecological risk and threaten the human health. Chlorinated pollutants are difficult to degrade and mineralize by the conventional advanced oxidation process as the C-Cl bond is resistant to reactive oxygen species oxidation. Herein, we designed a bifunctional Fe/Cu bimetallic single-atom catalyst anchored on N-doped porous carbon (FeCuSA-NPC) for the electro-Fenton process, in which chlorinated pollutants are dechlorinated on single-atom Cu and subsequently oxidized by the ·OH radical produced from O2 conversion on single-atom Fe. Benefitting from the synergistic effect between dechlorination on single-atom Cu and ·OH oxidation on single-atom Fe, the chlorinated organic pollutants can be efficiently degraded and mineralized. The mass activity for chlorinated organic pollutant degradation by FeCuSA-NPC is 545.1-1374 min-1 gmetal-1, excessing the highest value of the reported electrocatalyst. Moreover, FeCuSA-NPC is demonstrated to be pH-universal, long-term stable, and environment friendly. This work provides a new insight into the rational design of a bifunctional electrocatalyst for efficient removal of chlorinated organic pollutants.

Accidents involving hydrogen explosions occur frequently, yet systematic methods of explosion suppression have not been investigated and applied. Therefore, this paper studied the deflagration characteristics in hydrogen with the addition of propane in the tube filled with mesh aluminium alloys (MAAs). The effects of different propane contents and different filling densities (the mass of MAAs per unit volume in a vessel) on the explosion suppression of the premixed gas are examined. The results show that propane and MAAs can effectively suppress the hydrogen-air explosion. However, MAAs have multiple suppression/promotion effects on the propane-hydrogen explosion. Based on the mathematical model, the dominant effect of MAAs changes abruptly toward the promoting effect when the hydrogen content exceeds 72.26% of the premixed gas stoichiometric concentration. It is also found that an increase in filling density would have a beneficial effect on explosion suppression. The study results provide references for preventing hydrogen and hydrogenated hydrocarbon fuels explosions and optimizing the performance of MAAs.

In this paper, γ-Al2O3 supported nickel, manganese, cobalt, and other metal oxide catalysts were prepared by the impregnation method respectively, and its ozone catalytic decomposition performance was studied at 25°C under a WHSV of 200000 mL/(gcat·h). The results showed that 10% NiO/γ-Al2O3 catalyst demonstrates superior catalytic activity, and the ozone conversion rate is higher than 96% within 20 h. According to the characterizations of XRD, XPS, TEM, SEM-EDS and H2-TPR, its excellent ozone may be attributed to the formation of NiAl2O4 spinel on the surface of NiO/γ-Al2O3 catalyst. Furthermore, the mechanism of ozone decomposition on different transition metal oxide catalysts is divergent. The related study sheds new light on the reaction mechanism of ozone catalytic decomposition over transition metal oxides such as nickel and manganese, it also provides the guidelines for the development of efficient ozone decomposition catalysts.

Water splitting is considered as one of the recommendable techniques to realize clear and renewable hydrogen production. However, it suffers from lacking efficient and sustainable catalysts. Herein, a metal–organic framework/graphene oxide pyrolysis strategy was proposed to prepare nitrogen-doped porous carbon-stabilized alloys supported on reduced graphene oxide (PdCo@N–C/rGO) composite. When evaluated as an electrocatalyst for hydrogen evolution reaction (HER), the as-obtained PdCo@N–C/rGO shows an excellent performance in acidic media including positive onset potential close to that of commercial Pt/C (vs. SCE), low overpotential and Tafel slope, as well as long-term durability. Also, it delivers outstanding HER activities in alkaline and neutral conditions. The excellent performance could be mainly ascribed to their synergetic effect among alloy particles, nitrogen-doped porous carbon shell, and conductive rGO substrate. A metal-organic framework engineered strategy was proposed to prepare N-doped porous carbon-stabilized PdCo alloys supported on reduced graphene oxide nanocomposite. Specifically, the as-obtained catalyst delivers excellent electrochemical activity for hydrogen evolution reaction.

Pellino1 has been shown to regulate proinflammatory genes by activating the nuclear factor kappa B (NF-κB) and Toll-like receptor (TLR) signaling pathways, which are important in the pathological development of lipopolysaccharide (LPS)-induced myocarditis. However, it is still unknown whether silencing Pellino1 (si-Pellino1) has a therapeutic effect on this disease. Here, we showed that silencing Pellino1 can be a potential protective strategy for abnormal myocardial energy metabolism in LPS-induced myocarditis. We used liquid chromatography electrospray–ionization tandem mass spectrometry (LC–MS/MS) to analyze samples from si-Pellino1 neonatal rat cardiac myocytes (NRCMs) treated with LPS or left untreated. After normalization of the data, metabolite interaction analysis of matched KEGG pathway associations following si-Pellino1 treatment was applied, accompanied by interaction analysis of gene and metabolite associations after this treatment. Moreover, we used western blot (WB) and polymerase chain reaction (PCR) analyses to determine the expression of genes involved in regulating cardiac energy and energy metabolism in different groups. LC–MS-based metabolic profiling analysis demonstrated that si-Pellino1 treatment could alleviate or even reverse LPS-induced cellular damage by altering cardiomyocytes energy metabolism accompanied by changes in key genes (Cs, Cpt2, and Acadm) and metabolites (3-oxoocotanoyl-CoA, hydroxypyruvic acid, lauroyl-CoA, and NADPH) in NRCMs. Overall, our study unveiled the promising cardioprotective effect of silencing Pellino1 in LPS-induced myocarditis through fuel and energy metabolic regulation, which can also serve as biomarkers for this disease. Supplementary Information The online version contains supplementary material available at 10.1007/s00726-021-02978-w.

We demonstrate the ability of tetraalkylammonium borohydrides to capture large amounts of CO2 , even at low CO2 concentrations, and reduce it to formate under ambient conditions. These materials show CO2 absorption capacities up to 30 mmol CO 2 g-1 at room temperature and 1 bar CO2 . Every BH4 - anion can react with three CO2 molecules to form triformatoborohydride ([HB(OCHO)3 ]- ). The thermodynamics and kinetics of the reaction were monitored by a magnetic suspension balance (MSB). Direct CO2 capture and reduction from air was achieved with tetraethyl, -propyl, and -butylammonium borohydride. The alkyl chain length played an important role in the kinetics and thermodynamics of the reaction, especially in CO2 diffusivity (crystallinity and free-volume), activation energy (charge-transfer dependent on the alkyl chain), and hydrophobicity. Adding HCl gave formic acid and the corresponding chloride ammonium salt, which can be recycled. In addition, transfer of formate was achieved for the N-formylation of an amine.

A series of trace compounds (diamondoids, ethanodiamondoids, and thiadiamondoids) were detected through two-dimensional gas chromatography/time-of-flight mass spectrometry (GC × GC-TOFMS) analysis of Ordovician condensate samples from the Tazhong area. Gas chromatography-mass spectrometry (GC-MS) analysis showed that the biomarker parameters are less effective for high-maturity oils. Carbon isotope and geochemical features suggested that the gas is a high-temperature cracking gas when its temperature is higher than 170 °C. The H2S content is 8.27%, suggesting that it is affected by thermochemical sulfate reduction (TSR). However, the geological analysis indicated that the Ordovician reservoirs do not satisfy the conditions for TSR. The high-maturity oil in the Ordovician reservoirs may generate diamondoids and ethanodiamondoids when cracking, while TSR and severe cracking occur in deep Cambrian source rocks and produce a large number of diamondoids, ethanodiamondoids, organic sulfur compounds (OSCs), etc. The secondary geochemical products that are carried up by the dry gas and migrate upward through faults and are enriched in Ordovician crude oil reservoirs. On this basis, we proposed that the condensate presented was formed by the mixing of dry gas from Cambrian oil that was altered by cracking and TSR into Ordovician in situ slightly cracked oil, therefore speculating that the favorable reservoir–seal assemblages in this area may contain abundant oil and gas resources. Consequently, improved knowledge of secondary alteration effects on the reservoir and underground fluids is vital for oil and gas prediction and exploration development in the next step.

The migration of small molecular mass organic compounds from polypropylene (PP) copolymer films into food simulants during and after high pressure processing (HPP) was studied. An overlapping temperature profile was developed to isolate the pressure effect of HPP (700 MPa, 71°C, 5 min) from equivalent thermal processing (TP) at atmospheric pressure (0.1 MPa). Chloroform, toluene, methyl salicylate, and phenylcyclohexane were chosen as surrogate compounds, and were spiked into test polymer films at concentrations of 762-1152 mg kg

The relation between catalytic reactivities and metal/metal oxide ratios, as well as the functions of the metal and the metal oxides were investigated in the CO2 hydrogenation reaction over highly active Cox(CoO)1–x catalysts in operando. The catalytic reactivity of the samples in the CO2 methanation improves with the increased CoO concentration. Strikingly, the sample with the highest concentration of CoO, i.e., Co0.2(CoO)0.8, shows activity at temperatures lower than 200 °C where the other samples with less CoO are inactive. The origins of this improvement are the increased amount and moderate binding of adsorbed CO2 on CoO sites. The derivative adsorption species are found to be intermediates of the CH4 formation. The metallic Co functions as the electronically catalytic site which provides electrons for the hydrogenation steps. As a result, an abundant amount of CoO combined with Co is the optimal composition of the catalyst for achieving the highest reactivity for CO2 hydrogenation.

Five water-soluble flexible organic frameworks have been synthesized from a pyridinium-derived tetracationic tetraaldehyde and five diacylhydrazines (1 : 2) through the quantitative formation of a hydrazone bond in water at ambient temperature. Dynamic light scattering experiments reveal that the homogeneous frameworks display hydrodynamic diameters ranging from 68 nm to 167 nm, which can be tuned by changing the concentration of the components. Molecular modelling shows that, when adopting an ideal, extended conformation, the frameworks form an aperture of 4 nm diameter. The new flexible frameworks are generally of low cytotoxicity. Fluorescence imaging and flow cytometric analysis demonstrate that the new flexible porous frameworks can quickly include single and double stranded DNA of 21 nucleotides and deliver the included DNA into both normal and cancer cells, with the percentage of delivered cells reaching up to 99.5%.

Inverse-sandwich samarium and ytterbium biphenyl complexes were synthesized by the reduction of their trivalent halide precursors with potassium graphite in the presence of biphenyl. While the samarium complex had a similar structure as previously reported rare earth metal biphenyl complexes, with the two samarium ions bound to the same phenyl ring, the ytterbium counterpart adopted a different structure, with the two ytterbium ions bound to different phenyl rings. Upon the addition of crown ether to encapsulate the potassium ions, the inverse-sandwich samarium biphenyl structure remained intact; however, the ytterbium biphenyl structure fell apart with the concomitant formation of a divalent ytterbium crown ether complex and potassium biphenylide. Spectroscopic and computational studies were performed to gain insight into the electronic structures and bonding interactions of these samarium and ytterbium biphenyl complexes. While the ytterbium ions were found to be divalent with a 4f14 electron configuration and form a primarily ionic bonding interaction with biphenyl dianion, the samarium ions were in the trivalent state with a 4f5 electron configuration and mainly utilized the 5d orbitals to form a δ-type bonding interaction with the π* orbitals of the biphenyl tetraanion, showing covalent character., Inverse-sandwich samarium and ytterbium biphenyl complexes were synthesized and characterized by X-ray crystallography. Combined experimental and computational studies indicated that they have distinct electronic structures and bonding interactions.

Searching for novel alternatives to the traditional graphite anode in high performance lithium-ion batteries is of great significance, which, however, faces many challenges. In this work, pyrolysis coupled with a selenization strategy was adopted to synthesize a one-dimensional core–shell nanorod composite (MoO2/ZnSe@N-C) by using zeolitic-imidazole framework coated molybdenum trioxide as a precursor. The as-obtained material comprises a zinc selenide loaded molybdenum dioxide core and a nitrogen-doped carbon shell, which can enhance the specific capacity through conversion reactions and buffer the volume change as well as promote the electrical conductivity, respectively. When used as an anode in lithium-ion batteries, the optimized MoO2/ZnSe@N-C sample delivers a high specific capacity (807 mA h g−1 at 100 mA g−1 for 100 cycles) with a coulombic efficiency up to 99%, a good rate capability, and long-term cycling stability for 900 cycles at 500 mA g−1 which is better than that of MoO3 and ZIF-8 derived materials. In addition, the lithium storage mechanism was analyzed by cyclic voltammetry at various scanning rates and the result indicates that the capacitive-controlled behavior dominates the Li+ ion transport kinetics process.

Bis(N-ethylbenzimidazol-2-ylmethyl)allylamine (EtAIDB) and its two complexes, [Mn(EtAIDB)Cl2] (1) and [Zn(EtAIDB)Cl2] (2), have been synthesized and characterized by elemental analyses, molar conductivities, UV–Visible and IR spectra. The crystal structures of both complexes have been determined by X-ray single crystal diffraction. The coordination environment of Mn(II) in 1 is a five-coordinate distorted trigonal bipyramid with a N3Cl2 ligand set, while 2 is a four-coordinate twisted tetrahedral geometry. Structural and Hirshfeld surface analysis reveals that these two complexes are dimers formed by π···π interactions. The antioxidant activity was determined by superoxide methods in vitro, indicating that 1 exhibited potential antioxidant properties.

The multiscale structural, physicochemical, and digestible properties of potato starch before and after heat-moisture treatment were investigated, and further compared between repeated heat-moisture treatment (RHMT) and continuous heat-moisture treatment (CHMT). After heat-moisture treatment, there appeared partial disruption and pits on the starch granules, and the birefringence edges of HMT starch particles became blurred. Besides, the molecular weight of samples conspicuously decreased after two kinds of treatments. The crystal type of HMT starches transformed from B-type to C-type according to X-ray analysis. A decrease in the solubility and swelling power in high temperatures were identified. The pasting temperature, the gelatinization transition temperature (To , Tp , Tc ), and the slowly digestible starch (SDS) content of HMT starches were significantly higher than native potato starch, while the peak viscosity, the trough viscosity, the final viscosity, the breakdown, and the gelatinization enthalpy (ΔH) of RHMT and CHMT potato starches decreased compared to the native. RHMT potato starches displayed significantly higher relative crystallinity degree and gelatinization transition temperatures. The cooling process of RHMT in which the linkage between the recombinant amylose/amylopectin was enhanced compared with CHMT, which contributed to that RHMT potato starches exhibited greater advantages in practical applications. PRACTICAL APPLICATION: The described RHMT and CHMT starches provide new ideas for the study of modified starch. Furthermore, this study revealed the mechanism of heat-moisture processing provided some instructions to the application of RHMT potato starch.

The effects of continuous heat-moisture treatment (CHM) and repeated heat-moisture treatment (RHM) on multi-scale structure, physicochemical and digestibility properties of wheat A- and B-starch were investigated and compared. Both A- and B-starch granules maintained integrity after repeated and continuous modification. Changes in starch molecules induced the diversification of crystal structure and physicochemical properties. Crystal type of CHM and RHM starches maintained the original A-type while the crystallinity decreased after treatmnt. For wheat A-starch, the RS and RDS contents of RHM starches were obviously lower than native ones while the SDS content increased. Meanwhile, the RDS and SDS contents of treated B-starch were significantly higher than native ones but the RS content was lower. At the same conditions, B-starches exhibited a lower relative crystallinity, lower viscosity parameters, lower To, Tc, Tp and ΔH values than A-starches. In general, the repeated heat-moisture treated samples obtained superior characteristics than continuous treated ones, and the results of A- and B-starch varied greatly.

Three new metal complexes, namely: [Mn(AIDB)Cl2]·DMF (1), [Zn(AIDB)Br2]·CH3OH (2) and [Co(AIDB)Cl2]·CH3OH (3) having a ligand bis(benzimidazol-2-ylmethyl)allylamine (AIDB), have been synthesized in high yields and characterized by elemental analyses, molar conductivities, IR, UV–Vis spectra and single-crystal X-ray diffraction. The structural analysis revealed that all the three complexes 1–3 have five-coordinated trigonal bipyramid geometry where the degree of distorting is 1>3>2. In vitro antioxidant activity assay demonstrates that the complexes 1 and 3 display high scavenging activity against hydroxyl (OH·) and superoxide (O2−·) radicals.

As the most prevalent and abundant transcriptional modification in the eukaryotic genome, the continuous and dynamic regulation of N(6)-methyladenosine (m(6)A) has been shown to play a vital role in physiological and pathological processes of cardiovascular diseases (CVDs), such as ischemic heart failure (HF), myocardial hypertrophy, myocardial infarction (MI), and cardiomyogenesis. Regulation is achieved by modulating the expression of m(6)A enzymes and their downstream cardiac genes. In addition, this process has a major impact on different aspects of internal biological metabolism and several other external environmental effects associated with the development of CVDs. However, the exact molecular mechanism of m(6)A epigenetic regulation has not been fully elucidated. In this review, we outline recent advances and discuss potential therapeutic strategies for managing m(6)A in relation to several common CVD-related metabolic disorders and external environmental factors. Note that an appropriate understanding of the biological function of m(6)A in the cardiovascular system will pave the way towards exploring the mechanisms responsible for the development of other CVDs and their associated symptoms. Finally, it can provide new insights for the development of novel therapeutic agents for use in clinical practice.

A novel fluorescent probe, 2-allyl-6-((2-((2-hydroxy-5-nitrobenzylidene)amino)ethyl)amino)-1H-benzo[de]isoquinoline- 1,3(2H)-dione (ABID), based on naphthalimide-Schiff base, has been designed and synthesized for the monitoring of Cu2+ ions. In solution (DMSO/HEPES, 1:1, v/v, pH 7.4), ABID displayed fluorescence quenching towards Cu2+ ions over other important metal ions. A good linearity with a correlation coefficient (R2) of 0.99 validated that the ABID probe could be used to detect Cu2+ ions in 0.5–5.0 μM concentrations. The limit of detection of ABID for Cu2+ could reach at 3.4 × 10–7 M level, and the quenching constant (KSV) of ABID towards Cu2+ was calculated to be 3.4 × 104 M–1. The 2:1 stoichiometry and the binding mode between ABID and Cu2+ were studied by a Job plot and UV-Vis and fluorescence titration. Additionally, ABID was successfully employed to monitor Cu2+ in the Yellow River and tap water samples.

Efficient electroreduction of CO2 to multi-carbon products is a challenging reaction because of the high energy barriers for CO2 activation and C–C coupling, which can be tuned by designing the metal centers and coordination environments of catalysts. Here, we design single atom copper encapsulated on N-doped porous carbon (Cu-SA/NPC) catalysts for reducing CO2 to multi-carbon products. Acetone is identified as the major product with a Faradaic efficiency of 36.7% and a production rate of 336.1 μg h−1. Density functional theory (DFT) calculations reveal that the coordination of Cu with four pyrrole-N atoms is the main active site and reduces the reaction free energies required for CO2 activation and C–C coupling. The energetically favorable pathways for CH3COCH3 production from CO2 reduction are proposed and the origin of selective acetone formation on Cu-SA/NPC is clarified. This work provides insight into the rational design of efficient electrocatalysts for reducing CO2 to multi-carbon products. Efficient electroreduction of CO2 to multi-carbon products is challenging. Here, the single atom Cu encapsulated on N-doped porous carbon catalysts are designed for reducing CO2 to acetone at low overpotentials and the active sites are identified as Cu coordination with four pyrrole-N atoms.

The metal- and solvent-free capture and reduction of large amounts of CO2 to formate under ambient conditions is achieved by combining a pyrrolidinium-based ionic liquid with a borohydride anion. This material demonstrates one of the highest CO2 capacities at room temperature and 1 bar with up to 1 g CO 2 g-1 IL . CO2 gas reacts with the BH4 - anion to give triformatoborohydride, [HB(OCHO)3 ]- . The reaction occurs without loss in capacity at low CO2 concentration (6 vol % diluted with N2 ). The thermodynamics and kinetics of the reaction were monitored by using a magnetic suspended balance. In addition, more than 1 mol CO 2 mol-1 [ EMPY ] [ BH 4 ] is captured and reduced if air is used as a CO2 source. The product can be then treated with HCl to give formic acid and the corresponding ionic liquid chloride, which can be recycled. This ionic liquid borohydride demonstrates great potential as a CO2 absorber and reducer to produce alternative fuels.

Anisotropic colloidal particles with concave and convex structures are useful in both theoretical studies and applications. In this work, we mass-produced polystyrene (PS) colloidal particles with multiple concavities through dispersion polymerization techniques. By increasing the delayed feeding time td of the cross-linker divinylbenzene (DVB), the morphological evolution of particles can be classified into two stages, during which the formation of different concavities is consistent with either the buckling mechanism or phase separation mechanism. By varying the DVB dosage, we found that the size of the big chamber formed on the particle surfaces decreases as the DVB dosage increases. Then, using these concave particles as seeds, 2-5 μm anisotropic colloids with various shapes, including spherical, ellipsoidal, snowman and multi-protrusion, were synthesized by seeded emulsion polymerization. Moreover, our results show that both the chambers and long narrow ditches on the surface of seeds can be the active sites for monomers to gather and polymerize, but monomers in the big chamber have a priority to polymerize first when big and small concavities both exist on seeds. The results of this study could mean great potential in synthesizing a variety of anisotropic particles with well-controlled concave morphologies.

Lignin is a complex polymer in plant cell walls whose proportion is second only to that of cellulose and plays an important role in the mechanical properties of wood and stress resistance of plants. Here, we induced tension wood (TW) formation in Catalpa bungei by artificial bending and analyzed the lignin metabolism of the TW. LC-MS analysis showed that a significantly higher content of coniferyl aldehyde was observed in the TW cell wall than in the opposite wood (OW) and normal wood (NW) cell walls. TW had significantly lower contents of coniferyl alcohol than OW and NW. Raman spectroscopy results indicated that TW had lower total lignin than OW and NW. The transcription and translation levels of most of the differentially expressed genes (DEGs) involved in lignin monomer biosynthesis indicated upregulation in TW/OW and TW/NW. We found no significant difference in the transcription levels of three collision gases (CADs) between TW and OW or between NW, but their translation levels were significantly downregulated in TW, suggesting post-transcriptional control for CAD. We predicted and analyzed transcription factors that could target DEGs involved in lignin monomer biosynthesis in TW. Based on the analysis of the relationships of targeting and coexpression, we found that NAC (evm.model.group1.695) could potentially target 4CLs and CCoAOMT, that HD-Zip (evm.model.group7.1157) had potential targeting relationships with CCoAOMT, F5H, and CCR, and that their expression levels were significantly positive. It is speculated that the upregulation of NAC and HD-ZIP transcription factors activates the expression of downstream target genes, which leads to a significant increase in coniferyl aldehyde in TW. However, the decrease in total lignin in TW may be caused by the significant downregulation of CAD translation and the significant decrease in precursors (coniferyl alcohol). Whether the expression of CAD genes is regulated by post-transcriptional control and affects TW lignin metabolism needs further study.

Although the earliest animals might have evolved in certain “sweet spots” in the last 10 million years of Ediacaran (550–541 Ma), the Cambrian explosion requires sufficiently high levels of oxygen (O2) in the atmosphere and diverse habitable niches in the substantively oxygenated seafloor. However, previous studies indicate that the marine redox landscape was temporally oscillatory and spatially heterogeneous, suggesting the decoupling of atmospheric oxygenation and oceanic oxidation. The seawater sulfate concentration is controlled by both the atmospheric O2 level and the marine redox condition, with sulfide oxidation in continents as the major source, and sulfate reduction and pyrite burial as the major sink of seawater sulfate. It is thus important to quantify the sulfate concentration on the eve of the Cambrian explosion. In this study, we measured the pyrite contents and pyrite sulfur isotopes of black shale samples from the Yurtus Formation (Cambrian Series 2) in the Tarim Block, northwestern China. A numerical model is developed to calculate the seawater sulfate concentration using the pyrite content and pyrite sulfur isotope data. We first calibrate some key parameters based on observations from modern marine sediments. Then, the Monte Carlo simulation is applied to reduce the uncertainty raised by loosely confined parameters. Based on the geochemical data from both Tarim and Yangtze blocks, the modeling results indicate the seawater sulfate concentration of 8.9–14 mM, suggesting the seawater sulfate concentration was already 30–50% of the present level (28 mM). High seawater sulfate concentration might be attributed to the enhanced terrestrial sulfate input and widespread ocean oxygenation on the eve of the Cambrian explosion.

Myocardial infarction (MI), one of the most severe types of heart attack, exerts a strong negative effect on heart muscle by causing a massive and rapid loss of cardiomyocytes. However, the existing therapies do little to improve cardiac regeneration. Due to the role of methyltransferase-like 3 (METTL3) in the physiological proliferation of cardiomyocytes, we aimed to determine whether METTL3 could also promote cardiomyocyte proliferation under pathological conditions and to elucidate the underlying mechanism. The effects of METTL3 on cardiomyocyte proliferation and apoptosis were investigated in an in vivo rat model of MI and in an in vitro model of neonatal rat cardiomyocytes (NRCMs) exposed to hypoxia. We found that METTL3 expression was downregulated in hypoxia-exposed NRCMs and MI-induced rats. Furthermore, METTL3 pretreatment enhanced cardiomyocyte proliferation and inhibited cardiomyocyte apoptosis under hypoxic or MI conditions, and silencing METTL3 had the opposite effects. Additionally, METTL3 overexpression upregulated miR-17-3p expression. The miR-17-3p agomir mimicked the pro-proliferative and antiapoptotic effects of METTL3 in hypoxia-exposed cells or rats with MI, while the miR-17-3p antagomir blocked these effects. Additionally, pretreatment with the RNA-binding protein DGCR8 also hampered the protective role of METTL3 in hypoxia-exposed cells. Overall, the current study indicated that METTL3 could improve cardiomyocyte proliferation and subsequently ameliorate MI in rats by upregulating proliferation-related miR-17-3p in a DGCR8-dependent pri-miRNA-processing manner.

High cost and instability of platinum (Pt) counter electrodes (CEs) are two persistent issues in dye-sensitized solar cells (DSSCs). Here, ternary selenide RuCoSe and NiCoSe-nanostructured CEs are ...

Synthesis gas production via chemical-looping partial oxidation (CLPO) of methane reduces operating cost and likely avoids carbon dioxide emissions. Previous studies exhibit La0·7Sr0·3FeO3 (LSF) a good high-temperature oxygen carrier, but not being applicable in intermediate-temperature CLPO processes. This work proposes a CuO modified LSF (xCuO/LSF, x = 2,5,10,15) for enhancing the reactivity of oxygen carriers at relatively low temperatures. Characterization methods, including N2 physisorption, ICP-OES, H2-TPR, XRD and XPS, are implemented to determine properties of xCuO/LSF. Fixed-bed experiments determine the best candidate under 750 °C is 10CuO/LSF. The methane conversion rate of 10CuO/LSF is more than 3 times compared to that of unmodified LSF and the concentration of syngas increases by 375% with the H2/CO molar ratio of about 2.5. The regenerability of 10CuO/LSF proves to be good. This study provides a promising and simple way to lower the operating temperature of the CLPO process, likely leading a considerable energy saving.

Effects of repeated heat-moisture treatment (RHM) and continuous heat-moisture treatment (CHM) on structural, physicochemical, and digestibility properties of mung bean starch were investigated. Rupture and scallops appeared on the surface of starch granules and some polarization cross disappeared after CHM and RHM. Besides, CHM starch exhibited severe rupture than RHM with the same treatment time. Crystal type of CHM and RHM starch maintained A-type while crystallinity decreased first but then increased as treating time increased. Besides, the relative crystallinity, transition temperatures, ΔH, and slowly digestible starch and rapidly digestible starch content of RHM were significantly higher than CHM whereas solubility, swelling power, and pasting viscosities of RHM samples were lower than CHM under the same treating time. Overall, RHM measures have more advantages than CHM in the modification of the structural, physicochemical, and digestibility properties of starch.

An accurate, nondestructive, and economic prospecting technique is of utmost significance to explore petroleum resources in desert, however, the typically used technologies fail to provide direct and noninvasive detection. Here, we demonstrated a terahertz (THz) prospecting method for predicting the distribution of oil reservoir by extracting the sands from the surface areas in a desert oilfield. The accuracy of THz prospecting reached to more than 80%. The trace organic matters migrating from underground reservoir to surface sands can be detected by THz spectroscopy, which was the mechanism of THz spectroscopy for reservoir exploration. The long-chain alkanes, nitro organics, and aromatic compounds were also confirmed by thermogravimetric analysis system coupled with Fourier transform infrared and mass spectroscopy. When the trace organics were decomposed from sands, the THz response was equivalent to that of other sands. Consequently, the petroleum prospecting method on the basis of THz spectroscopy is useful for the improvement and optimization of geophysical exploration system in desert.

It is well known that excessive levels of sulfur dioxide and its derivatives are connected to diverse diseases. Therefore, developing highly sensitive probes to detect and monitor sulfite in living cells is important for the diagnosis of disease and the study of biochemical processes in vivo. In this report, two zero cross-talk ratiometric fluorescent probes were synthesized (CA-ID-MC and CA-BI-MC), which were derived from carbazole-indolenine π-conjugated system for effective detection of sulfite in living cells. Observably, CA-BI-MC exhibited the largest emission shift of 157 nm from 617 to 460 nm with the addition of various concentrations of sulfite, which is beneficial for high-resolution imaging of the sulfite. CA-BI-MC also exhibits high sensitivity and low cytotoxicity. More importantly, this probe successfully located mitochondria and sensed the sulfite in HeLa cells caused by exogenous stimulation.

Background: Bladder cancer is one of the most frequent urologic tumours in the world. MicroRNA- 200c (miR-200c) has been considered a regulator of tumour angiogenesis. Akt2/mTOR was considered a regulator of vascular endothelial growth factor (VEGF) and hypoxia-inducible factor 1α (HIF-1α). However, the mechanism by which miR-200c regulates bladder cancer angiogenesis remains unknown. Methods: Western blotting and qRT-PCR were used to detect the expression of protein and mRNA, respectively. Cell proliferation, migration and invasion were detected using MTT, wound-healing and transwell assays, respectively. A dual luciferase reporter assay was used to identify the binding site between miR-200c and Akt2. A tube formation assay was also applied to detect the angiogenesis ability. Results: Significantly higher expression levels of HIF-1α and VEGF and lower levels of miR-200c were observed in three types of bladder cancer cell lines. Transfection with the miR-200c mimic markedly inhibited cell viability, angiogenesis, and the expression of VEGF and HIF-1α. Overexpression of miR-200c remarkably suppressed the expression of Akt2, and the binding site between them was identified. Knockdown of Akt2 remarkably decreased the expression of VEGF and HIF-1α by regulating mTOR. miR-200c influenced the expression of VEGF and HIF-1α through the Akt2/mTOR signalling pathway and further regulated angiogenesis in bladder cancer cells. Conclusions: We proved that miR-200c could suppress HIF-1α/VEGF expression in bladder cancer cells and inhibit angiogenesis, and these regulations were achieved by targeting Akt2/mTOR. This study may provide new insight into the prevention and treatment of bladder cancer.

In this article, a new “turn-off” fluorescent sensor N- n-butyl-4-{2-[(ethylimino)methyl]phenol}-1,8-naphthalimide (HL) for CuII ions is synthesized, which contains a 1,8-naphthalimide moiety as the fluorophore and a Schiff base as the recognition group. As expected, it exhibits high selectivity and sensitivity for detecting CuII ions over other common metal ions in acetonitrile–2-(4-(2-hydroxyethyl)-1-piperazinyl)-ethanesulfonic acid (HEPES) (1:1 v/v, pH = 7.4) solution. In addition, the fluorescence intensity for HL showed a good linearity with the concentration of CuII ions in the range of 0.5–5.0 μM. The 2:1 binding stoichiometry between HL and CuII ions was established on the basis of combined fluorescence titrations, a Job’s plot, single-crystal X-ray analysis and mass spectrometry. The quenching response of HL toward CuII ions is attributed to the reverse photoinduced electron transfer mechanism. The proposed sensor HL is preliminarily applied to quantify CuII ions in water samples from the Yellow River and tap water.

A three-dimensional interconnected reticular porous carbon (3D-RPC) with a large surface area of 1535 m2 g–1 by a sol–gel method followed by carbonation as well as a chemical activation process usi...

Electro-Fenton is considered as a promising technology for treating of wastewater from industrial, and its performance can be significantly influenced by the H2O2 production on cathode catalysts. However, the catalysts developed recently suffer disadvantages of either poor H2O2 production activity or high cost for preparing catalysts. A low-cost and high-efficient electrocatalyst with high yield of H2O2 production is desirable for the treatment of real wastewater. In this work, a cost-efficient catalyst was fabricated by fluorination of commercial activated carbon. The fluorinated activated carbon possessed enhanced H2O2 production rate of 37.9 mg L−1 min−1 (−0.4 V vs. SCE). As a result, nearly 100% of phenol was degraded within 15 min with a kinetic constant of 0.32 min−1 at pH 3 (−0.4 V vs. SCE). Moreover, the COD of real secondary effluent from coking was decreased from 320 to 92 mg L−1 within 2 h, which met the discharge standard of the coking chemical industry (GB 16171-2012; COD

Two mononuclear Cu(I) complexes, [Cu(PBO)(PPh3)2]·PF6·CH2Cl2 (1) and [Cu(PBM)(PPh3)2]·PF6 (2) (PBO = 2-(2′-pyridyl)benzoxazole, PBM = 2-(2′-pyridyl)benzimidazole, PPh3 = triphenylphosphine)...

Transition metal oxide thin films and heterostructures have attracted remarkable and continuous attention due to the incredible variety of electronic and magnetic properties. A significant challeng...

A series of ZrO2 materials were prepared by calcining ZrO2·xH2O at temperatures from 600 to 900 °C. The oxide materials were used to prepare Pd/ZrO2 catalysts coated on the monolith. Under lean conditions, the monolithic catalysts were tested for complete oxidation of CH4 in the presence and absence of water. In process of the preparation of supports, the ratio of monoclinic ZrO2 (m-ZrO2) to tetragonal ZrO2 (t-ZrO2) increased with calcination temperature. Strong interaction between palladium and ZrO2 further induced the transformation of t-ZrO2 to m-ZrO2 when supporting Pd on ZrO2. Phase transformation in samples including ZrO2 supports and Pd/ZrO2 catalysts was accompanied by an increase in the concentration of surface oxygen vacancies, improving the mobility of oxygen species over the samples. It was found that the Pd catalyst using ZrO2 calcined at 900 °C as the support had the highest oxygen vacancy concentration among the four catalysts as synthesized. Under dry reaction conditions, this catalyst showed considerably higher activity in methane oxidation promoted by oxygen vacancies. However, under wet reaction conditions (10 vol% H2O), water poisoned the surface-active sites for all the catalysts. The promoting effect of increasing oxygen vacancies on the activity of CH4 oxidation was thus weakened significantly by the water poisoning, resulting in slight differences in activity among the catalysts.

Reaction of 2,2-(1,4-butanediyl)bis-1,3-benzoxazole (BBO) or 2-(2′-pyridyl)benzoxazole (PBO) ligands with [Cu(CH3CN)2(PPh3)2](BF4) afforded a copper(I) coordination polymer {[Cu(BBO)(PPh3)](BF4)}n (1) and a mononuclear copper(I) complex [Cu(PBO)(PPh3)2](BF4)·2CH2Cl2 (2) (where PPh3 = triphenylphosphine), which have been characterized by elemental analysis, IR spectra and single-crystal X-ray diffraction. The structural analysis revealed that in complex 1, copper(I) ions are three-coordinated and the geometric structure around the central copper(I) atom can be described as planar trigonal configuration. Complex 1 exhibits an one-dimensional coordination polymer by two BBO bridging adjacent copper(I) ions, forming a single-stranded meso-helical chain structure. Mononuclear complex 2 is four-coordinated and slightly distorted triangular-pyramid geometry. Solid luminescence properties investigation show that complex 1 has two emission peaks, which attributed to the π*-π and π*-n transitions. However complex 2 only has one emission peak, which may be attributed to MLCT [d10(Cu)→π*]. This indicates that different types of N-heterocyclic ligands have an important influence on the structure and luminescent properties of copper(I) complexes.

Turnip of the Brassica genus is a traditional crop that is widely cultivated in farming and farming-pastoral regions in Tibet. It is mostly utilized as animal fodder and vegetable around the Tibetan plateau. Given their high altitudes and variable climate types, different regions of Tibet plateau are home to a rich diversity of turnip. A mass of studies related to genetic diversity of highland crops have been carried out in recent years. However, the genetic diversity of Tibetan turnip remains to be elucidated to date. In this study, we performed morphological investigation and simple sequence repeat analysis, to characterize the genetic diversity and population structure of Tibetan turnips. Then, we explored the physiological response of seedlings under low-temperature stress. We also performed a field experiment, to identify clubroot-resistant cultivars. Results showed significant differences in phenotypic traits among different sources of 25 Tibetan turnip accessions. The genetic similarity dendrogram showed that the genetic distance in the 25 accessions was between 0.61 and 0.77. When the similarity coefficient is between 0.644 and 0.646, they can be divided into three subgroups, and they presented a certain relationship between geographical origin and its genetic distance. The central diffusion location suggests that the genetic diversity and population structure of these Tibetan turnip accessions are consistent with their geographical origin. In addition, the potential clubroot resistance accession is 156-13, and the chilling resistance accessions are 156-8 and 156-10. These results suggest the Tibetan turnip is a valuable resource for the genetic analysis and breeding of new clubroot-resistant cultivars.

In order to realize real-time monitoring of Cu2+, a new fluorescent probe HL, a Schiff base derivative of N-n-butyl-4-[2]-1,8-naphthalimide, has been designed and synthesized. In methanol-HEPES [2-(4-(2-hydroxyethyl)-1-piperazinyl)-ethanesulfonic acid] solution (1:1, v/v, pH = 7.4) HL showed excellent selectivity towards Cu2+ over other common coexisting metal ions. The fluorescence intensity for HL showed a good linearity with the concentration of Cu2+ ions in the range of 0.5–5.0 μm. Based on combined fluorescence titration, Job’s plot analysis, and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry results, Cu2+ forms a 1:2 complex with L. The fluorescence intensity of HL exhibits significant quenching after binding with Cu2+, owing to the strong, intrinsic paramagnetic behavior of Cu2+. Ultimately, in order to test the performance of the synthesized probe, HL was preliminarily applied to the determination of Cu2+ in the Yellow River and in tap water with satisfying results.

Fast pyrolysis is a comparable technology with enzyme or acid hydrolysis for saccharification of biomass. The low yield of levoglucosan and the formation of inhibitors to biocatalysts from lignocellulose hamper the fermentable utilization of pyrolysate. In this study, aiming to enhance the production of levoglucosan, dilute alkali pretreatment was performed prior to fast pyrolysis of corncobs. The yield of levoglucsoan from pretreated corncobs was significantly improved (34.8%) as compared to that from un-treated corncobs (3.0%), which was mainly attributed to the removal of alkaline and alkaline earth metals as well as lignin fraction by NaOH pretreatment. Conversely, NaOH pretreatment suppressed the formation of acids (from 11.1 to 2.2%), furans (from 2.5 to 2.0%), ketones (from 15.7 to 9.8%) and phenols (from 4.8 to 1.3%), which were common inhibitors to the biocatalysts. Accordingly, NaOH pretreatment facilitated further selective conversion of biomass in fast pyrolysis and made the pyrolysate more fermentable.

In this paper, a new short process integrating carbochlorination and electrolyzation to produce metallic titanium in molten NaCl–CaCl2 electrolyte was presented. This electrochemical experiment was carried out at 1123 K using carbon-doped TiO2 precursors. The electrolysis process of intermediate produced by carbochlorination of carbon-doped TiO2 precursors was studied. The cathodic product was analyzed using X-ray diffraction (XRD), inductively coupled plasma atomic emission spectroscopy (ICP-AES) and scanning electron microscopy (SEM) after electrolysis. The evolved gas was analyzed by a gas chromatograph equipped with a thermal conductivity detector (GC-TCD). Results showed that Ti powder of 98.7% could be obtained as the final product in the cathode by electrolysis for 5 h at 4.0 V using raw pellets with a C/TiO2 mass ratio of 0.15. Furthermore, the electrochemical process of Ti deposition was comprehensively evaluated by cyclic voltammetry and squarewave voltammetry. The electrode reaction mechanisms and particle evolution principles in molten salt during this electrolysis process were discussed. It indicated that titanium chloride in lower valence (TiCl3) with more productive advantage could exist as an intermediate, and Ti3+ ions were reduced to Ti metal by a two-step mechanism corresponding to the pathway: Ti3+ → Ti2+ → Ti.

1,2-Bis(benzimidazol-2-yl)ethane (bbe) and its transition metal complexes, [Cu(bbe)Cl2]·DMF (1) and [Zn(bbe)Cl2]2(2), have been synthesized and characterized by elemental analysis, UV–Vis and IR spectra. X-ray crystal structure analysis revealed that both complexes have four-coordinate, distorted tetrahedral geometries. Complex 2 has two crystallographically independent but chemically identical Zn(bbe)Cl2 units. The cyclic voltammogram of complex 1 shows an irreversible Cu2+/Cu+ couple. In vitro antioxidant tests showed that complex 1 has significant antioxidant activity against superoxide. Photoluminescence investigations showed that complex 2 exhibits light blue (441 nm) photoluminescence. Compared with the free bbe proligand, a redshift of 16 nm was observed for complex 2, which may be attributed to π*–π transitions.

Chemical looping steam reforming (CLSR) is a novel technology for hydrogen production using metal oxide as an oxygen carrier (OC). During the CLSR, the OC (MeO) is first reduced to the final state ...

The objective of this study was to build an efficient outer-inner looping redox reaction mechanism called steam recycled biomass chemical looping gasification (SR-BCLG) for H2 production by using BaFe2O4 as an oxygen carrier (OC). The X-ray diffraction (XRD) results showed the phase changes of BaFe2O4 in the SR-BCLG process can be oxidized to its initial state stimulated by steam. In addition, the impacts on the temperature, water injection rate (steam/biomass ratio) and OC loading were investigated. The maximum H2 production of 28.5 mol/kg· biomass was achieved in the 60 min of gasification with a BaFe2O4 load amount of 10 wt%, which is an increase in H2 production of 109.6% compared with the no-OC biomass gasification process under the optimal conditions. Durative high production of H2-enriched syngas was obtained during the cyclic stability tests, indicating the significant redox durability and high H2-generation properties of BaFe2O4. The XRD, scanning electron microscopy (SEM), and thermo-gravimetric analyzer (TG) characterizations revealed the high stability of BaFe2O4, which can be ascribed to the existence of Ba2+. The bimetal functional BaFe2O4 allows for an innovative method of outer-inner looping redox reactions for continuous H2-enriched syngas generation in the SR-BCLG process.

The double perovskite oxides (DPOs) LaSrFe2-xCoxO6 (x = 0, 0.2, 0.4, 0.6, 0.8) were investigated as oxygen carriers for the chemical looping steam methane reforming (CL-SMR). The fresh oxides were prepared by micro-emulsion method and their physical and chemical properties were characterized by X-ray diffraction, H2-temperature programmed reduction and X-ray photoelectron spectroscopy technologies. Meanwhile, isothermal reactions for methane reforming and steam splitting were carried out in a fixed-bed reactor to determine the influences of Co-substitution on the reactivity of LaSrFe2-xCoxO6. The substitution of metal Co has no obvious effect on the crystal structure of double perovskite, but induces a certain degree of Fe/Co disorder generating oxygen vacancies and/or higher oxidation states of metal cations. Synergistic interaction between surface metal ions, such as (Fe4+/Fe5+-O2--Co2+) and (Fe3+-O2--Co3+), plays a positive effect for the dissociation of methane. The activity may be more likely to be associated with the active oxygen species in connection with Co species on the DPOs surface and abundant of syngas was generated due to the concordant of methane dissociation with the lattice oxygen diffusion. Comprehensively considered, an optimal range of the degree of Co substitution is x = 0.4–0.6 for LaSrFe2-xCoxO6, probably converting 70% of CH4 into CO and H2 with molar ratio around 2:1. At the reduced states, the ability of DPOs for steam splitting is primarily associated with the oxygen vacancies after oxygen consumption. The substitution of metal Co slightly enhances the hydrogen production capacity and resistance to carbon formation, achieving the average hydrogen yields at 2.89–3.33 mmol/g oxygen carrier and 1.46–1.61 wt% of carbon depositions.

A novel marine origin Bacillus subtilis strain H1 isolated from a shrimp culture pond effectively removed NH₄⁺‐N, NO2-‐N and NO3-‐N, with a maximum ammonium, nitrite and nitrate removal rate of 2.35 mg NH₄⁺‐N L⁻¹ hr⁻¹ per OD, 9.64 mg NO2-‐N L⁻¹ hr⁻¹ per OD and 0.75 mg NO3-‐N L⁻¹ hr⁻¹ respectively. The gas chromatography–isotope ratio mass spectrometry results indicated that N₂O was emitted when ¹⁵NH₄Cl, Na¹⁵NO₂ or Na¹⁵NO₃ was used. Additionally, N₂ was also produced when Na¹⁵NO₂ was used. Single‐factor experiments suggested that the optimal conditions for NH₄⁺‐N and NO2-‐N removal were glucose as a carbon source, C/N 15, initial pH 7.5, 30 g/L NaCl, 28°C and a shaking speed of 160 rpm. Orthogonal tests showed that the optimal conditions for NH₄⁺‐N removal were C/N 15, pH 9, 10 g/L NaCl and shaking speed 160 rpm when ammonium chloride was used as the substrate. The optimal conditions for NO2-‐N removal were C/N 10, pH 6, 10 g/L NaCl and a shaking speed of 160 rpm when sodium nitrite was used as the substrate. In summary, B. subtilis strain H1 had highly efficient aerobic nitrifying–denitrifying ability and high adaptability, suggesting that it is potentially valuable to marine aquaculture.

Chemical-looping steam methane reforming (CL-SMR) is a novel technology for syngas and hydrogen production without purification process. A series of three-dimensionally ordered macroporous (3DOM) LaFe1−xNixO3 (x = 0.05, 0.1, 0.15, 0.2, 0.25, 0.3) perovskite-type oxides were synthesized using the polystyrene colloidal crystal templating method. The structural and physico-chemical properties of the obtained oxides were investigated by scanning electron microscopy (SEM), X-ray diffraction (XRD) and Brunauere-Emmette-Teller (BET) surface area technologies. The structure-reactivity relationships and effects of Ni-substitution on the improvement of reactivity and resistance to carbon formation were investigated in a thermo-gravimetric analyzer and a fixed-bed reactor. It was found that the as-prepared oxides obtained standard perovskite structures and the well-ordered skeleton was surrounded with uniform close-packed macroporous windows. Ni-substitution improved the ability for oxygen supply but simultaneously enhanced the methane dissociation. While the openness channel and large surface area of 3DOM perovskite allowed low mass-transfer resistances and provided high active sites for reaction. Complicated factors synergistically affected the reactivity and an optimal value for Ni-substitution is confirmed with x = 0.1 by comprehensively considering from the points of reactivity, resistance to carbon formation, as well as hydrogen generation capacity. During the following successive redox reactions, 3DOM LaFe0.9Ni0.1O3 exhibited good regenerability and thermo-stability probably converting 90% of CH4 into syngas in methane reforming stage and generating ∼210–220 ml hydrogen in steam splitting stage.

Reaction of 2-(2′-pyridyl)benzoxazole (2-PBO), 2-(4′-pyridyl)benzoxazole (4-PBO) and 2,2-(1,4-butanediyl)bis-1,3-benzoxazole (BBO) ligands with CuX (X = I, Br, SCN) afforded a binuclear copper(I) complex [Cu(2-PBO)(μ2-I)]2 (1) and three copper(I) coordination polymers [Cu4(4-PBO)4(μ3-I)4]n (2), {[Cu(4-PBO)(μ3-SCN)]2}n (3) and {[Cu(BBO)(μ2-Br)]2}n (4). The structural analysis revealed that the all copper(I) ions are four-coordinated and the geometric structure around the central copper(I) atom possessing slightly distorted tetrahedral geometry in complexes 1–4. Halogen or pseudohalide ions can not only act as counter anions, but also as ligands participation in coordination when the cuprous ion coordination sites are not saturated. Due to the different coordination modes of the benzoxazole ligands, in order to satisfy the tetra-coordination of cuprous ions, halogen or pseudohalide ions adopt μ2 and/or μ3-bridging modes to synergistically complete coordination. Photoluminescence investigation show that complexes 1, 3 and 4 have two emission peaks, the high energy band peak is attributed to MLCT[d10(Cu)→π*] and XMCT, the low energy band peak is caused by the 3CC emission. This may be due to the presence of μ2-X (X = I, Br, S) in these complexes. However complex 2 only had one emission peak, which may be attributed to MLCT[d10(Cu)→π*] and XMCT.