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Designing highly active and cost-effective electrocatalysts for the alkaline hydrogen oxidation reaction (HOR) is critical for advancing anion-exchange membrane fuel cells (AEMFCs). While dilute metal alloys have demonstrated substantial potential in enhancing alkaline HOR performance, there has been limited exploration in terms of rational design, controllable synthesis, and mechanism study. Herein, we developed a series of dilute Pd-Ni alloys, denoted as x% Pd-Ni, based on a trace-Pd decorated Ni-based coordination polymer through a facile low-temperature pyrolysis approach. The x% Pd-Ni alloys exhibit efficient electrocatalytic activity for HOR in alkaline media. Notably, the optimal 0.5% Pd-Ni catalyst demonstrates high intrinsic activity with an exchange current density of 0.055 mA cm-2, surpassing that of many other alkaline HOR catalysts. The mechanism study reveals that the strong synergy between Pd single atoms (SAs)/Pd dimer and Ni substrate can modulate the binding strength of proton (H)/hydroxyl (OH), thereby significantly reducing the activation energy barrier of a decisive reaction step. This work offers new insights into designing advanced dilute metal or single-atom-alloys (SAAs) for alkaline HOR and potentially other energy conversion processes.
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AIM: The diagnosis of alcoholic liver disease (ALD) is still a great challenge. Therefore, the purpose of this study is to identify and characterize new metabolomic biomarkers for the diagnosis and staging of ALD. METHODS: A total of 127 patients with early liver injury, 40 patients with alcoholic cirrhosis (ALC) and 40 healthy controls were included in this study. Patients with early liver injury included 45 patients with alcoholic liver disease (ALD), 40 patients with non-alcoholic fatty liver disease (NAFLD) and 40 patients with viral liver disease (VLD). The differential metabolites in serum samples were analyzed using ultra-high-performance liquid chromatography-quadrupole/time-of-flight mass spectrometry, and partial metabolites in the differential metabolic pathway were identified by liquid chromatography- tandem mass spectrometry. RESULTS: A total of 40 differential metabolites and five differential metabolic pathways in the four groups of patients with early liver disease and healthy controls were found, and the metabolic pathway of primary bile acid (BA) biosynthesis was the pathway that included the most differential metabolites. Therefore, 22 BA profiles were detected. The results revealed that the changes of BA profiles were most pronounced in patients with ALD compared with patients with NAFLD and VLD, in whom 12 differential BAs were diagnostic markers of ALD (AUC = 0.883). The 19 differential BAs in ALC and ALD were diagnostic markers of the stage of alcoholic hepatic fibrosis (AUC = 0.868). CONCLUSION: BA profiles are potential indicators in the diagnosis of ALD and evaluation of different stages.
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Hepatopatias Alcoólicas , Hepatopatia Gordurosa não Alcoólica , Humanos , Ácidos e Sais Biliares , Hepatopatias Alcoólicas/diagnóstico , Cirrose Hepática , BiomarcadoresRESUMO
Exploring highly active and stable bifunctional water-splitting electrocatalysts at ultra-high current densities is remarkably desirable. Herein, 3D nickel-iron phosphides nanosheets modified by MnOx nanoparticles are grown on nickel foam (MnOx /NiFeP/NF). Resulting from the electronic coupling effect enabled by interface modifications, the intrinsic activities of the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) are improved. Meanwhile, 3D nanosheets provide abundant active sites for HER and OER, leading to accelerating the reaction kinetics. Besides, the shell-protection characteristic of MnOx improves the durability of MnOx /NiFeP/NF. Therefore, MnOx /NiFeP/NF shows exceptional bifunctional electrocatalytic activities toward HER (an overpotential of 255 mV at 500 mA cm-2 ), OER (overpotentials of 296 and 346 mV at 500 and 1000 mA cm-2 , respectively), and overall water splitting (cell voltages of 1.796 and 1.828 V at 500 and 1000 mA cm-2 , respectively). Furthermore, it owns remarkably outstanding stability for overall water splitting at ultra-high current densities (120 and 70 h at 500 and 1000 mA cm-2 , respectively), which outperforms almost all of the non-noble metal electrocatalysts. This work presents efficient strategies of interface modifications, 3D nanostructures, and shell protection to afford ultra-high current densities.
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The extensive use of the broad-spectrum antibiotics like oxytetracycline (OTC) has become a serious environmental issue globally. OTC has profound negative effects on aquatic organisms including fishes. In this study, RNA-Seq analysis was employed to examine the possible molecular mechanism of hepatotoxicology in zebrafish induced by OTC exposure. Adult male zebrafish was exposed to 0, 5, 90, and 450 µg/L OTC for 3 weeks. The results showed the decrease in body weight and tail length but the increase in total length of zebrafish under OTC exposure in a dose-dependent way. In addition, severe histopathological damages were featured by increasing tissue vacuolization in the livers of 450 µg/L OTC group. Moreover, RNA-Seq analysis revealed that molecular signaling and functional pathways in the liver were disrupted by OTC exposure. Furthermore, the down-regulation of gene expression after OTC exposure was found on both the genes related to fatty acid degradation and the genes related to lipid synthesis. The present study implied that OTC induced liver malfunction and fish health risks through growth retard, histopathological damages, molecular signaling disruption, genetic expression alteration, and lipid metabolism disturbance.
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Oxitetraciclina , Animais , Antibacterianos/toxicidade , Metabolismo dos Lipídeos , Masculino , Oxitetraciclina/toxicidade , Transcriptoma , Peixe-Zebra/fisiologiaRESUMO
The TDM of voriconazole which exhibits wide inter-individual variability is indispensable for treatment in clinic. In this study, a method that high-performance liquid chromatography tandem mass spectrometry cubed (HPLC-MS3) is first built and validated to quantify voriconazole in human plasma. The system is composed of Shimadzu Exion LCTM UPLC coupled with a Qtrap 5500 mass spectrometer. The separation of voriconazole is performed on a Poroshell 120 SB-C18 column at a flow rate of 0.8 mL/min remaining 7 min for each sample. The calibration curves are linear in the concentration range of 0.25-20 µg/mL. Intra-day and inter-day accuracies and precisions are within 8.0% at three concentrations, and the recoveries and matrix effect are all within accepted limits. In terms of stability, there is no significant degradation of voriconazole under various conditions. The HPLC-MS3 and HPLC-MRM (multiple reaction monitoring) methods are compared in 42 patients with Passing-Bablok regression and Bland-Altman plots, and the results show no significant difference between the two methods. However, HPLC-MS3 has a higher S/N (signal-to-noise ratio) and response than the MRM. Finally, the HPLC-MS3 assay is successfully applied to monitor the TDM (therapeutic drug monitoring) of voriconazole in human plasma, and this verifies that the dosing guidelines for voriconazole have been well implemented in the clinic and patients have received excellent treatment.
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Monitoramento de Medicamentos , Espectrometria de Massas em Tandem , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida/métodos , Monitoramento de Medicamentos/métodos , Humanos , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem/métodos , VoriconazolRESUMO
We use computational materials methods to study the sequential appearance of zinc-based zeolitic imidazolate frameworks (ZIFs) generated in the mechanochemical conversion process. We consider nine ZIF topologies, namely RHO, ANA, QTZ, SOD, KAT, DIA, NEB, CAG and GIS, combined with the two ligands 2-methylimidazolate and 2-ethylimidazolate. Of the 18 combinations obtained, only six (three for each ligand) were actually observed during the mechanosynthesis process. Energy and porosity calculations based on density functional theory, in combination with the Ostwald rule of stages, were found to be insufficient to distinguish the experimentally observed ZIFs. We then show, using classical molecular dynamics, that only ZIFs withstanding quasi-hydrostatic pressure P ≥ 0.3 GPa without being destroyed were observed in the laboratory. This finding, along with the requirement that successive ZIFs be generated with decreasing porosity and/or energy, provides heuristic rules for predicting the sequences of mechanically generated ZIFs for the two ligands considered.
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Zeolitas , Imidazóis/química , Simulação de Dinâmica Molecular , Zeolitas/química , ZincoRESUMO
High-performance electrocatalysts are critical to support emerging electrochemical energy storage and conversion technologies. Graphite-derived materials, including fullerenes, carbon nanotubes, and graphene, have been recognized as promising electrocatalysts and electrocatalyst supports for the oxygen reduction reaction (ORR), oxygen evolution reaction (OER), hydrogen evolution reaction (HER), and carbon dioxide reduction reaction (CO2RR). Effective modification/functionalization of graphite-derived materials can promote higher electrocatalytic activity, stability, and durability. In this review, the mechanisms and evaluation parameters for the above-outlined electrochemical reactions are introduced first. Then, we emphasize the preparation methods for graphite-derived materials and modification strategies. We further highlight the importance of the structural changes of modified graphite-derived materials on electrocatalytic activity and stability. Finally, future directions and perspectives towards new and better graphite-derived materials are presented.
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Fluorination is considered as a means of reducing the degradation of Fe/N/C, a highly active FeNx-doped disorganized carbon catalyst for the oxygen reduction reaction (ORR) in PEM fuel cells. Our recent experiments have, however, revealed that fluorination poisons the FeNx moiety of the Fe/N/C catalytic site, considerably reducing the activity of the resulting catalyst to that of carbon only doped with nitrogen. Using the density functional theory (DFT), we clarify in this work the mechanisms by which fluorine interacts with the catalyst. We studied 10 possible FeNx site configurations as well as 2 metal-free sites in the absence or presence of fluorine molecules and atoms. When the FeNx moiety is located on a single graphene layer accessible on both sides, we found that fluorine binds strongly to Fe but that two F atoms, one on each side of the FeNx plane, are necessary to completely inhibit the catalytic activity of the FeNx sites. When considering the more realistic model of a stack of graphene layers, only one F atom is needed to poison the FeNx moiety on the top layer since ORR hardly takes place between carbon layers. We also found that metal-free catalytic N-sites are immune to poisoning by fluorination, in accordance with our experiments. Finally, we explain how most of the catalytic activity can be recovered by heating to 900 °C after fluorination. This research helps to clarify the role of metallic sites compared to non-metallic ones upon the fluorination of FeNx-doped disorganized carbon catalysts.
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The uneven consumption of anions during the lithium (Li) deposition process triggers a space charge effect that generates Li dendrites, seriously hindering the practical application of Li-metal batteries. We report on a cobalt phthalocyanine electrolyte additive with a planar molecular structure, which can be tightly adsorbed on the Li anode surface to form a dense molecular layer. Such a planar molecular layer cannot only complex with Li ions to reduce the space charge effect, but also suppress side reactions between the anode and the electrolyte, producing a stable solid electrolyte interphase composed of amorphous lithium fluoride (LiF) and lithium carbonate (LiCO3 ), as verified by X-ray absorption near-edge spectroscopy. As a result, the Li|Li symmetric cell exhibits excellent cycling stability above 700â h under a high plating capacity of 3â mAh cm-2 . Moreover, the assembled Li|lithium iron phosphate (LiFePO4 , LFP) full-cell can also deliver excellent cycling over 200â cycles under lean electrolyte conditions (3â µL mg-1 ).
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CO2 reduction reaction (CO2 RR) provides a promising strategy for sustainable carbon fixation by converting CO2 into value-added fuels and chemicals. In recent years, considerable efforts are focused on the development of transition-metal (TM)-based catalysts for the selectively electrochemical CO2 reduction reaction (ECO2 RR). Co-based catalysts emerge as one of the most promising electrocatalysts with high Faradaic efficiency, current density, and low overpotential, exhibiting excellent catalytic performance toward ECO2 RR for CO and HCOOH productions that are economically viable. The intrinsic contribution of Co and the synergistic effects in Co-hybrid catalysts play essential roles for future commercial productions by ECO2 RR. This review summarizes the rational design of Co-based catalysts for ECO2 RR, including molecular, single-metal-site, and oxide-derived catalysts, along with the nanostructure engineering techniques to highlight the distribution of the ECO2 RR products by Co-based catalysts. The density functional theory (DFT) simulations and advanced in situ characterizations contribute to interpreting the synergies between Co and other materials for the enhanced product selectivity and catalytic activity. Challenges and outlook concerning the catalyst design and reaction mechanism, including the upgrading of reaction systems of Co-based catalysts for ECO2 RR, are also discussed.
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In order to guarantee the species correction of Notopterygium seeds, a molecular identification method with ITS2 as DNA barcode has been verified. In this study, 27 samples of Notopterygium seeds were collected from the main producing area of Notopterygium. The morphological characteristics of the Notopterygium seeds were firstly surveyed. Then the DNA extraction, PCR amplification, DNA sequencing and DNA assembly were carried out. The species identification for a Notopterygium seed was implemented through distance method, NJ-tree method and the DNA barcoding system for traditional Chinese medicine (www.tcmbarcode.cn). The results showed that the seeds of N. incisum and N. franchetii had similar morphological characteristics and were difficult to distinguish clearly based on morphological descriptions. With the results of molecular identification, 24 samples were genuine including 13 N. incisum seeds samples and 11 N. franchetii genuine seeds samples. In conclusion, DNA barcode technology can accurately and efficiently identify the species of Notopterygium seeds. Furthermore, this study will provide a new method for germplasm resources identification of medicinal materials and supplies some guidelines for establishing Chinese herbal seeds and seedlings quality standards.
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Apiaceae/genética , Código de Barras de DNA Taxonômico/métodos , Apiaceae/classificação , China , DNA de Plantas/genética , Filogenia , Sementes/classificação , Sementes/genéticaRESUMO
Inert atmosphere is normally necessary for fabrication of solid composite electrolytes (SCEs) as a crucial part of solid-state Li-metal batteries in order to avoid undesirable reactions induced by ambient moisture. Herein, we developed an air-processable technique to fabricate SCEs by employing LiCF3SO3 (LiOTf) as the Li salt, which was combined with Li6.4La3Zr1.4Ta0.6O12 (LLZTO) as the fast Li-conductor and polyvinylidene difluoroethylene/polyvinyl acetate (PVDF/PVAC) as the polymer matrix. With the assistance of trace H2O dissolved in electrolyte solution, the room-temperature Li+ conductivity of the obtained aSCE reached as high as 5.09 × 10-4 S cm-1, which was over 3 orders of magnitude higher than that of the one (iSCE, 1.93 × 10-7 S cm-1) cast by the electrolyte solution prepared in an inert atmosphere. The theoretical calculation results reveal that the oxygen atom of H2O exhibits a high propensity to interact with the Li atom in LiOTf (Li···O), thereby establishing a hydrogen bond with the oxygen atom (H···O) in N,N-dimethylformamide (solvent). Such interactions promoted the dissociation of LiOTf and led to the formation of uniform Li+ transportation channels. Simultaneously, the composition distribution was also altered, resulting in a smoother surface of aSCE and lowered crystallinity of PVDF. On this basis, the LiOTf/LLZTO/PVDF/PVAC solution at 60 °C was directly coated onto the surface of the LiFePO4 (LFP) cathode to fabricate the LFP-aSCE film after drying in an oven. The assembled LFP-aSCE/Li battery wetted by trace sulfolane exhibited an initial Coulombic efficiency of 94.7% and a capacity retention rate of up to 96% at 0.2 C (137 mAh g-1) after 180 cycles and a high capacity of 143.7 mAh g-1 at 0.5 C (150 cycles). Overall, this work could pave the way for the facile fabrication of solid electrolytes.
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θ-Defensins are the only natural cyclic proteins found in primates. They have strong antimicrobial activity related to their trisulfide ladders and macrocyclic conformation. A non-cyclic baboon θ-defensin (BTD) was synthesized by substituting valine with phenylalanine at position 17, at the C-terminal end of the BTD; this was termed "BTD-S." The antimicrobial activities of this synthetic peptide were investigated against Escherichia coli and two cotton phytopathogens: Verticillium dahliae and Fusarium oxysporum. The minimum inhibitory concentration (MIC) of BTD-S for E. coli was 10 µg/mL and for V. dahliae was 5 µg/mL, significantly lower than that for F. oxysporum (40.0 µg/mL). A time course analysis of fungal cultures indicated that the growth of V. dahliae was completely inhibited after 96 h of BTD-S treatment. Furthermore, hemolysis assays revealed that BTD-S was not toxic to mammalian cells as it could not induce lysis of sheep red blood cells even at ten times the MIC (50 µg/mL). Scanning electron microscopy and double-stained (calcofluor white and propidium iodide binding) fluorescence microscopy showed that exposure of spores of V. dahliae to BTD-S either disabled normal germination or disintegrated the spores. The size of cells exposed to BTD-S was significantly reduced compared with controls, and their number increased in a dose-dependent curve when measured by flow cytometry. These findings suggest that BTD-S has great potential to inhibit the growth of V. dahliae and can be utilized as an effective remedy to control economic losses caused by Verticillium wilt in the development of wilt-resistant cotton.
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Anti-Infecciosos/farmacologia , Defensinas/biossíntese , Defensinas/farmacologia , Fusarium/efeitos dos fármacos , Papio/metabolismo , Verticillium/efeitos dos fármacos , Animais , Anti-Infecciosos/química , Defensinas/química , Defensinas/genética , Eritrócitos/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Hemólise , Testes de Sensibilidade Microbiana , Ovinos , Esporos Fúngicos/efeitos dos fármacos , Fatores de TempoRESUMO
Birds are sensitive to environmental pollution and lead (Pb) contamination could negatively affect nearly all avian organs and systems including kidney of excretive system. Thereby, we used a biological model species-Japanese quail (Coturnix japonica) to examine the nephrotoxic effects of Pb exposure and possible toxic mechanism of Pb on birds. Quail chicks of 7-day-old were exposed to 50 ppm Pb of low dose and high dose of 500 ppm and 1000 ppm Pb in drinking water for five weeks. The results showed that Pb exposure induced kidney weight increase while body weight and length reduction. The increase of uric acid (UA), creatinine (CREA) and cystatin c (Cys C) in the plasma suggested renal dysfunction. Moreover, both microstructural and ultrastructural changes demonstrated obvious kidney damages. In particular, renal tubule epithelial cells and glomeruli swelling indicated renal inflammation. Furthermore, changes in the content and activity of oxidative stress markers suggested that Pb caused excessive oxidative stress in the kidney. Pb exposure also induced abnormal apoptosis in the kidney. In addition, RNA sequencing (RNA-Seq) analysis revealed that Pb disturbed molecular pathways and signaling related with renal function. Especially, Pb exposure resulted in an increase in renal uric acid synthesis by disrupting purine metabolism. Pb caused apoptotic increment by inhibiting the phosphatidylinositol-3-kinase (PI3K)/RAC-alpha serine/threonine-protein kinase (AKT) pathway and induced aggravated inflammation by activating Nuclear Factor kappa B (NF-κB) signaling pathway. The study implied that Pb caused nephrotoxicity through structural damages, uric acid metabolism disorder, oxidation imbalance, apoptosis and inflammatory pathway activation.
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Coturnix , NF-kappa B , Animais , NF-kappa B/metabolismo , Coturnix/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Chumbo/toxicidade , Fosfatidilinositol 3-Quinase/metabolismo , Ácido Úrico/metabolismo , Ácido Úrico/farmacologia , Estresse Oxidativo , InflamaçãoRESUMO
Regulating the local configuration of atomically dispersed transition-metal atom catalysts is the key to oxygen electrocatalysis performance enhancement. Unlike the previously reported single-atom or dual-atom configurations, we designed a new type of binary-atom catalyst, through engineering Fe-N4 electronic structure with adjacent Co-N2C2 and nitrogen-coordinated Co nanoclusters, as oxygen electrocatalysts. The resultant optimized electronic structure of the Fe-N4 active center favors the binding capability of intermediates and enhances oxygen reduction reaction (ORR) activity in both alkaline and acid conditions. In addition, anchoring M-N-C atomic sites on highly graphitized carbon supports guarantees of efficient charge- and mass-transports, and escorts the high bifunctional catalytic activity of the entire catalyst. Further, through the combination of electrochemical studies and in-situ X-ray absorption spectroscopy analyses, the ORR degradation mechanisms under highly oxidative conditions during oxygen evolution reaction processes were revealed. This work developed a new binary-atom catalyst and systematically investigates the effect of highly oxidative environments on ORR electrochemical behavior. It demonstrates the strategy for facilitating oxygen electrocatalytic activity and stability of the atomically dispersed M-N-C catalysts.
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High-performance oxygen electrocatalysts play a key role in the widespread application of rechargeable Zn-air batteries (ZABs). Single-atom catalysts (SACs) with maximum atom efficiency and well-defined active sites have been recognized as promising alternatives of the present noble-metal-based catalysts for oxygen reduction reaction and oxygen evolution reaction. To improve their oxygen electrocatalysis activities and reveal the structure-activity relationship, many advanced synthesis and characterization methods have been developed to study the effects of 1) coordination and electronic structure of the metal centers and 2) morphology and stability of the conductive substrates. Herein, a detailed review of the recent advances of SACs with strong electronic metal-support interaction (EMSI) for rechargeable ZABs is provided. Great emphasis was placed on the EMSI forms and design strategies. Moreover, the importance and the impact of the atomic coordinating structure and the substrates on the oxygen electrocatalytic activity and stability are highlighted. Finally, future directions and perspectives on the development of SACs are also presented.
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HIGHLIGHTS: Three-dimensional (3D) core-shell heterostructured NixSy@MnOxHy nanorods grown on nickel foam (NixSy@MnOxHy/NF) were successfully fabricated via a simple hydrothermal reaction and a subsequent electrodeposition process. The fabricated NixSy@MnOxHy/NF shows outstanding bifunctional activity and stability for hydrogen evolution reaction and oxygen evolution reaction, as well as overall-water-splitting performance. The main origins are the interface engineering of NixSy@MnOxHy, the shell-protection characteristic of MnOxHy, and the 3D open nanorod structure, which remarkably endow the electrocatalyst with high activity and stability. Exploring highly active and stable transition metal-based bifunctional electrocatalysts has recently attracted extensive research interests for achieving high inherent activity, abundant exposed active sites, rapid mass transfer, and strong structure stability for overall water splitting. Herein, an interface engineering coupled with shell-protection strategy was applied to construct three-dimensional (3D) core-shell NixSy@MnOxHy heterostructure nanorods grown on nickel foam (NixSy@MnOxHy/NF) as a bifunctional electrocatalyst. NixSy@MnOxHy/NF was synthesized via a facile hydrothermal reaction followed by an electrodeposition process. The X-ray absorption fine structure spectra reveal that abundant Mn-S bonds connect the heterostructure interfaces of NixSy@MnOxHy, leading to a strong electronic interaction, which improves the intrinsic activities of hydrogen evolution reaction and oxygen evolution reaction (OER). Besides, as an efficient protective shell, the MnOxHy dramatically inhibits the electrochemical corrosion of the electrocatalyst at high current densities, which remarkably enhances the stability at high potentials. Furthermore, the 3D nanorod structure not only exposes enriched active sites, but also accelerates the electrolyte diffusion and bubble desorption. Therefore, NixSy@MnOxHy/NF exhibits exceptional bifunctional activity and stability for overall water splitting, with low overpotentials of 326 and 356 mV for OER at 100 and 500 mA cm-2, respectively, along with high stability of 150 h at 100 mA cm-2. Furthermore, for overall water splitting, it presents a low cell voltage of 1.529 V at 10 mA cm-2, accompanied by excellent stability at 100 mA cm-2 for 100 h. This work sheds a light on exploring highly active and stable bifunctional electrocatalysts by the interface engineering coupled with shell-protection strategy.
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Developing cheap and earth-abundant electrocatalysts with high activity and stability for oxygen reduction reactions (ORRs) is highly desired for the commercial implementation of fuel cells and metal-air batteries. Tremendous efforts have been made on doped-graphene catalysts. However, the progress of phosphorus-doped graphene (P-graphene) for ORRs has rarely been summarized until now. This review focuses on the recent development of P-graphene-based materials, including the various synthesis methods, ORR performance, and ORR mechanism. The applications of single phosphorus atom-doped graphene, phosphorus, nitrogen-codoped graphene (P, N-graphene), as well as phosphorus, multi-atoms codoped graphene (P, X-graphene) as catalysts, supporting materials, and coating materials for ORR are discussed thoroughly. Additionally, the current issues and perspectives for the development of P-graphene materials are proposed.
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Bupleuri Radix is the dry root of certain species of the genus Bupleurum and is commonly used in traditional Chinese medicine. The increasing global demand for Bupleuri Radix cannot be fulfilled with wild populations only. Therefore, cultivated Bupleurum is now the main commercial source of this medicinal product. Different species of Bupleurum show different medicinal properties and clinical effects, making reliable authentication and assignment of correct botanical origin for medicinal species critical. However, accurate identification of the cultivated Bupleurum species is difficult due to dramatic morphological variations resulting from cultivation. In this study, we sampled 56 cultivated Bupleurum populations of six different morphotypes (Types A-F) from the main production areas of China, and 10 wild populations of four species were used as reference materials. Conventional DNA barcoding was conducted to identify cultivated Bupleurum species. Additionally, verification based on complete chloroplast genomes was performed and new chloroplast markers were developed and evaluated. The combination of these methods resulted in the successful identification of all cultivated Bupleurum individuals. Three chloroplast regions are recommended as additional barcodes for the genus: ycf4_cemA, psaJ_rpl33, and ndhE_ndhG. This is a reliable and promising strategy that can be applied to the authentication of natural products and the identification of other medicinal plant species with similar taxonomic problems.
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Bupleurum , Genoma de Cloroplastos , Plantas Medicinais , Humanos , Código de Barras de DNA Taxonômico , Raízes de Plantas/genética , Plantas Medicinais/genética , Medicina Tradicional Chinesa , Bupleurum/genéticaRESUMO
Three kinds of Pt anchoring on heteroatom-doped graphene were synthesised and their effects on catalytic performance were discussed. The introduction of N and P into graphene is helpful to decrease the Pt particle size with a homogeneous distribution and favor the electronic configuration for the ORR.