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Ba0.5Sr0.5Co0.8Fe0.2O3-δ (BSCF) perovskite has been recognized as a promising oxygen evolution reaction (OER) catalyst due to its superior intrinsic catalytic activity. However, BSCF suffers from serious degradation during the OER process due to its surface amorphization caused by the segregation of A-site ions (Ba2+ and Sr2+). Herein, we construct a novel BSCF composite catalyst (BSCF-GDC-NR) by anchoring the gadolinium-doped ceria oxide (GDC) nanoparticles on the surface of a BSCF nanorod by a concentration-difference electrospinning method. Our BSCF-GDC-NR has greatly improved bifunctional oxygen catalytic activity and stability toward both oxygen reduction reaction (ORR) and OER compared with the pristine BSCF. The improvement of the stability can be related to that anchoring GDC on BSCF effectively suppresses the segregation and dissolution of A-site elements in BSCF during the preparation and catalytic processes. The suppression effects are ascribed to the introduction of compressive stress between BSCF and GDC, which greatly inhibits the diffusions of Ba and Sr ions. This work can give a guidance for developing the perovskite oxygen catalysts with high activity and stability.
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Removing large concentrations of organic pollutants from water efficiently and quickly under visible light is essential to developing photocatalytic technology and improving solar energy efficiency. This study used a simple hydrothermal method to prepare a non-metallic, S-doped NaTaO3 (S-NTO) photocatalyst, which was then loaded onto biochar (BC) to form a S-NTO/BC composite photocatalyst. After uniform loading onto BC, the S-NTO particles transformed from cubic to spherical. The photogenerated electron-hole pair recombination probability of the composite photocatalyst was significantly lower than those of the NTO particles. The light absorption range of the catalyst was effectively widened from 310 nm UV region to visible region. In addition, a dual-effect catalytic system was constructed by introducing peroxymonosulfate (PMS) into the environment of the pollution to be degraded. The Rhodamine B, Methyl Orange, Acid Orange 7, tetracycline, and ciprofloxacin degradation efficiency at 40 mg/L reached 99.6%, 99.2%, 84.5%, 67.1%, and 70.7%, respectively, after irradiation by a 40 W lamps for 90 min. The high-efficiency visible-light catalytic activity of the dual-effect catalytic system was attributed to doping with non-metallic sulfur and loading of catalysts onto BC. The development of this dual-effect catalytic system provides new ideas for quickly and efficiently solving the problem of high-concentration organic pollution in aqueous environments, rationally and fully utilizing solar energy, and expanding the application of photocatalytic technology to practice.
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Poluentes Ambientais , Catálise , Carvão Vegetal , LuzRESUMO
Multi-component metal sulfide heterostructures are promising for multi-functional catalytic activities. In this work, we fabricated a multi-component metal sulfide heterostructure (Co-S-INF, composed of Co3S4 and (Fe, Ni)9S8) with nanoflower morphology clustered with numerous nanosheets by the electrodeposition of cobalt on iron-nickel foam followed by hydrothermal sulfurization treatment. Co-S-INF possesses high multi-functional electrocatalytic properties toward the oxygen evolution reaction (OER), oxygen reduction reaction (ORR), hydrogen evolution reaction (HER), and methanol oxidation reaction (MOR). In particular, the ORR potential at 10 mA cm-2 is 0.682 V, and the OER, HER, and MOR potentials at 100 mA cm-2 are 1.478 V, 0.289 V, and 1.417 V, respectively. By using Co-S-INF, the aqueous ZAB with an ultrahigh peak power density of 332.30 mW cm-2 and an overall water splitting (OWS) device with a low splitting voltage of 1.82 V at 100 mA cm-2 can be obtained. In addition, the OWS potential can be further decreased to 1.70 V at a current density of 100 mA cm-2 with the assistance of MOR at the anode accompanying the production of the high value-added formate. Our work opens the way for the application and development of multi-functional electrocatalysts.
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Objective: Based on real-world research, we aimed to evaluate the effectiveness and economy of recombinant human thrombopoietin (rhTPO) and recombinant human interleukin 11 (rhIL-11) in the treatment of cancer therapy induced thrombocytopenia (CTIT). Methods: We retrospectively collected clinical data of patients with CTIT who were treated with rhTPO or rhIL-11 in a single cancer hospital from January 2020 to December 2021. Propensity score matching (PSM) was applied to eliminate confounding factors. The measurements of effectiveness analysis were the platelet compliance rate, days of medication, days of compliance, highest platelet count after medication, platelet count elevation before and after medication, and the lowest platelet count after next-cycle cancer therapy. The economic evaluation was performed according to the results of the effectiveness evaluation. At the same time, patients were stratified according to type of tumor and grade of thrombocytopenia for subgroup analysis. Results: A total of 262 patients were collected and 174 patients were enrolled after PSM, 87 in the rhTPO group and 87 in the rhIL-11 group. In all patients, there were no significant differences in the platelet compliance rate, mean days of medication, median days of compliance, median highest platelet count after medication, and the median platelet count elevation before and after medication between the two groups (p > 0.05), but the median lowest platelet count after next-cycle cancer therapy in the rhTPO group was lower than that in the rhIL-11 group (p = 0.014). The subgroup analysis showed that the rhTPO group had longer mean days of medication than the rhIL-11 group in patients with hematological malignancies (p = 0.042), and a lower median lowest platelet count after next-cycle cancer therapy in patients with grade I/II thrombocytopenia than rhIL-11 group (p = 0.022), with no significant difference in other outcome indicators (p > 0.05). As there was no statistically significant difference in platelet compliance rate between the two groups, the cost-minimization analysis showed that the rhIL-11 group had lower treatment costs than the rhTPO group. Conclusion: RhTPO and rhIL-11 showed similar effectiveness in the treatment of CTIT, but rhIL-11 was more advantageous in economic cost.
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As a potential oxygen evolution reaction (OER) catalyst, Co-based perovskites have received intensive attention. However, Sr readily accumulates on their surface, and makes them inert toward the OER. Herein, we propose a simple but versatile electrochemical reduction method to reconstruct the active surface of Co-based perovskites within a few seconds. By this method, Sr rapidly precipitates from Co-based perovskites, accompanied by the introduction of Sr and oxygen vacancies. After reconstruction, the electrochemical active surface areas of Co-based perovskites greatly increase, and the OER overpotential of the optimized SrNb0.1Co0.7Fe0.2O3-δ (ER-SNCF-20s) reaches 278 mV at 10 mA cm-2. This can be explained by the decrease of overpotentials at the rate-determining step. Using ER-SNCF-20s, the splitting voltage of alkaline natural seawater can reach 1.56 V at 10 mA cm-2, and remains steady for 300 h. This effort offers a feasible method for reconstructing the active surface of Co-based perovskites.
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Endowing photocatalytic materials with a broader range of light responses is important for improving their performance and solar energy utilization. In this study, a simple sol-gel method was used to prepare Yb3+/Tm3+-co-doped Y2O3 upconversion materials and Y2O3:Yb3+, Tm3+/ZnO (Y/Z) composite photocatalysts for the photocatalytic degradation of dyes. The Y/Z composite photocatalyst achieved degradation rates of 38%, 95%, and 89% for methyl orange, methylene blue (MB), and acid chrome blue K dye solutions, respectively, within 30 minutes. The degradation efficiency for MB after three cycles of degradation was 86%. The spherical Y2O3:Yb3+, Tm3+ particles had diameters of 20-50 nm and attached to the ZnO nanosheets, forming a heterojunction structure with ZnO. Fluorescence spectroscopy showed that Y2O3:Yb3+, Tm3+ could convert near-infrared (NIR) light into three sets of ultraviolet light (290, 320, and 360 nm) under NIR excitation. Photoluminescence spectroscopy demonstrated that the photogenerated electron-hole pair recombination probability of the composite photocatalyst was significantly lower than that of ZnO nanosheets, thereby reducing the energy loss during the migration process. Furthermore, the addition of Y2O3:Yb3+, Tm3+ to ZnO substantially improved the absorption capacity for ultraviolet light, which enhanced the photocatalytic activity. A possible mechanism for the enhanced photocatalytic performance of the Y/Z composites was proposed based on the synergistic effect of heterojunction formation and the photoconversion process. The composite photocatalyst with upconversion characteristics and heterogeneous structure provides a new strategy for removing organic pollutants from water.
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The lipophilic prodrug of hydrophobic drugs with well-designed molecular structures can form stable pure prodrug nanoparticles (NPs), but rapid NPs aggregation in plasma greatly restricted their direct use for intravenous chemotherapy. To address this, DSPE-mPEG2000 and Cremophor EL are two of the most widely used lipophilic PEG derivatives to enhance their colloidal stability in plasma. However, their drug delivery performances have never been comparatively studied. Here, a redox-responsive lipophilic prodrug of SN38 was chosen as the model drug for such comparative investigations. We found that Cremophor EL/NPs having a small diameter (â¼15 nm) and poor kinetic stability displayed an enhanced cell internalization, higher cytotoxicity and prolonged circulation time as compared with DSPE-mPEG2000/NPs. Most importantly, these superiorities further resulted in a much more potent antitumor activity in CT26 colorectal cancer xenograft, but the increased loss of body weight was also noted. These results suggested that Cremophor EL could be more advantageous than DSPE-mPEG2000 in terms of the improvement of antitumor activity, but the enhanced toxicity warranted further attention in the future study.
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Neoplasias Colorretais/tratamento farmacológico , Sistemas de Liberação de Medicamentos , Irinotecano/administração & dosagem , Nanopartículas , Animais , Linhagem Celular Tumoral , Neoplasias Colorretais/patologia , Portadores de Fármacos/química , Glicerol/análogos & derivados , Glicerol/química , Interações Hidrofóbicas e Hidrofílicas , Irinotecano/química , Irinotecano/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Tamanho da Partícula , Fosfatidiletanolaminas/química , Polietilenoglicóis/química , Pró-Fármacos , Ratos , Ratos Sprague-Dawley , Inibidores da Topoisomerase I/administração & dosagem , Inibidores da Topoisomerase I/química , Inibidores da Topoisomerase I/farmacologia , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
A phytochemical investigation of the ethanolic extracts of the dried roots of Euphorbia nematocypha resulted in the isolation of a new phenylpropanoid, 16-O-caffeoyl-16-hydroxylhexadecanoic acid (1), together with 23 known compounds (2-24). Their structures were elucidated on the basis of spectroscopic data. Compound 1 was first to be isolated as a caffeic acyl long chain alkyl acid from the family Euphorbiaceae. The new isolated phenylpropanoid showed potent cytotoxic activities against the MCF-7 and HeLa cell lines.