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1.
Angew Chem Int Ed Engl ; : e202407612, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39007237

RESUMO

The synthesis of multicarbon (C2+) products remains a substantial challenge in sustainable CO2 electroreduction owing to the need for sufficient current density and faradaic efficiency alongside carbon efficiency. Herein, we demonstrate ampere-level high-efficiency CO2 electroreduction to C2+ products in both neutral and strongly acidic (pH = 1) electrolytes using a hierarchical Cu hollow-fiber penetration electrode (HPE). High concentration of K+ could concurrently suppress hydrogen evolution reaction and facilitate C-C coupling, thereby promoting C2+ production in strong acid. By optimizing the K+ and H+ concentration and CO2 flow rate, a faradaic efficiency of 84.5% and a partial current density as high as 3.1 A cm-2 for C2+ products, alongside a single-pass carbon efficiency of 81.5% and stable electrolysis for 240 h were demonstrated in a strong acidic solution of H2SO4 and KCl (pH = 1). Experimental measurements and density functional theory simulations suggested that tensile-strained Cu HPE enhances the asymmetric C-C coupling to steer the selectivity and activity of C2+ products.

2.
Micromachines (Basel) ; 15(4)2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38675325

RESUMO

Real-time DOA (direction of arrival) estimation of surface or underwater targets is of great significance to the research of marine environment and national security protection. When conducting real-time DOA estimation of underwater targets, it can be difficult to extract the prior characteristics of noise due to the complexity and variability of the marine environment. Therefore, the accuracy of target orientation in the absence of a known noise is significantly reduced, thereby presenting an additional challenge for the DOA estimation of the marine targets in real-time. Aiming at the problem of real-time DOA estimation of acoustic targets in complex environments, this paper applies the MEMS vector hydrophone with a small size and high sensitivity to sense the conditions of the ocean environment and change the structural parameters in the adaptive adjustments system itself to obtain the desired target signal, proposes a signal processing method when the prior characteristics of noise are unknown. Theoretical analysis and experimental verification show that the method can achieve accurate real-time DOA estimation of the target, achieve an error within 3.1° under the SNR (signal-to-noise ratio) of the X channel of -17 dB, and maintain a stable value when the SNR continues to decrease. The results show that this method has a very broad application prospect in the field of ocean monitoring.

3.
ACS Omega ; 8(49): 46569-46576, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38107883

RESUMO

As one of the most important derivatives of propylene, the production of propylene oxide (PO) is severely restricted. The traditional chlorohydrin process is being eliminated due to environmental concerns, while processes such as Halcon and hydrogen peroxide epoxidation are limited by cost and efficiency, making it difficult to meet market demand. Therefore, achieving PO production through clean and efficient technologies has received extensive attention, and halogen-mediated electrochemical epoxidation of alkene is considered to be a desirable technology for the production of alkylene oxide. In this work, we used electrochemical methods to synthesize PO in halogen-mediated systems based on a RuO2-loaded Ti (RuO2/Ti) anode and screened out two potential mediated systems of chlorine (Cl) and bromine (Br) for the electrosynthesis of PO. At a current density of 100 mA·cm-2, both Cl- and Br-mediated systems delivered PO Faradaic efficiencies of more than 80%. In particular, the Br-mediated system obtained PO Faradaic efficiencies of more than 90% at lower potentials (≤1.5 V vs RHE) with better electrode structure durability. Furthermore, detailed product distribution investigations and DFT calculations suggested hypohalous acid molecules as key reaction intermediates in both Cl- and Br-mediated systems. This work presents a green and efficient PO production route with halogen-mediated electrochemical epoxidation of propylene driven by renewable electricity, exhibiting promising potential to replace the traditional chlorohydrin process.

4.
Small ; 19(35): e2301338, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37183302

RESUMO

Electroreduction of CO2 to CO is a promising route for greenhouse gas resource utilization, but it still suffers from impractical current density and poor durability. Here, a nanosheet shell (NS) vertically standing on the Ag hollow fiber (NS@Ag HF) surface formed by electrochemical surface reconstruction is reported. As-prepared NS@Ag HF as a gas penetration electrode exhibited a high CO faradaic efficiency of 97% at an ultra-high current density of 2.0 A cm-2 with a sustained performance for continuous >200 h operation. The experimental and theoretical studies reveal that promoted surface electronic structures of NS@Ag HF by the nanosheets not only suppress the competitive hydrogen evolution reaction but also facilitate the CO2 reduction kinetics. This work provides a feasible strategy for fabricating robust catalysts for highly efficient and stable CO2 reduction.

5.
Medicine (Baltimore) ; 101(15): e29109, 2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35475798

RESUMO

BACKGROUND: When it comes to preterm newborns, respiratory distress syndrome (RDS) is the most frequent respiratory condition. Despite the fact that it is well acknowledged that preterm delivery plays a significant role, the causes of lung damage are still not completely understood. In newborns with extremely low birth weight and neonatal RDS, nasal continuous positive airway pressure has been suggested as the first respiratory assistance for spontaneous breathing. In the current research, we aim to carry out a meta-analysis to assess the effectiveness and safety of high-flow nasal cannula (HFNC) and non-invasive continuous positive airway pressure (nCPAP) in patients with neonatal respiratory distress syndrome (NRDS). METHODS: We intend to search the following databases: PubMed, EMBASE, Cochrane Library, Wanfang database, China National Knowledge Infrastructure (CNKI), and Google Scholar, starting from their initial publication until February 2022, to identify randomized controlled trials comparing HFNC to nCPAP in patients with NRDS. The suitable papers will be chosen by 2 writers who will work independently of one another. Using the Cochrane updated technique for risk of bias, each included article will be subjected to an independent data extraction process by the 2 writers who will then independently evaluate the risk of bias. Consequently, a third author will be asked to address any discrepancies that may arise between the writers. It will be necessary to pool the data and do a meta-analysis with the help of the RevMan 5.3 software. RESULTS: In this study, the effectiveness and safety of HFNC will be compared with those of nCPAP in patients with NRDS. CONCLUSION: If the results of this research are confirmed, they may serve as a summary of the most recent data for non-invasive respiratory assistance in NRDS. ETHICS AND DISSEMINATION: The study will require ethical approval. REGISTRATION NUMBER: DOI 10.17605/OSF.IO/BKSQ5.


Assuntos
Pressão Positiva Contínua nas Vias Aéreas , Síndrome do Desconforto Respiratório do Recém-Nascido , Cânula , Pressão Positiva Contínua nas Vias Aéreas/métodos , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Metanálise como Assunto , Síndrome do Desconforto Respiratório do Recém-Nascido/terapia , Revisões Sistemáticas como Assunto
6.
Entropy (Basel) ; 23(8)2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-34441169

RESUMO

A novel cooling, heating, and power system integrated with a solid oxide fuel cell and biomass gasification was proposed and analyzed. The thermodynamic models of components and evaluation indicators were established to present energetic and exergetic analysis. After the validations of thermodynamic models, the system performances under design work conditions were evaluated. The proposed system's electrical, energy, and exergy efficiencies reached up to 52.6%, 68.0%, and 43.9%, respectively. The gasifier and fuel cell stack were the most significant components of exergy destruction in this system, accounting for 41.0% and 15.1%, respectively, which were primarily caused by the gasification and electrochemical reactions' irreversibility. The influences of the key parameters of the ratio of steam to biomass mass flow rate (S/B), the biomass flow rate (Mbio), and the temperature and pressure of the fuel cell (Top and Psofc) on system energy performances were analyzed: doubling S/B (from 0.5 to 1.0) reduced the energy efficiency by 5.3%, while increasing the electrical efficiency by 4.6% (from 52.6% to 55.0%) and raising the biomass mass flow rate by 40% increased the energy and exergy efficiencies by 2.4% and 2.1%, respectively. When raising the SOFC operating temperature by 31.3%, the energy and exergy efficiencies rose by 61.2% (from 50.0% to 80.6%) and 45.1% (from 32.8% to 47.6%), respectively, but this likely would result in a higher operating cost. Increasing the SOFC pressure from 2 to 7 bar increased the electrical efficiency by 10.6%, but additional energy for pumping and compression was consumed.

7.
Medicine (Baltimore) ; 100(24): e26250, 2021 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-34128852

RESUMO

BACKGROUND: Asthma is the most frequently occurring obstructive airway disease, it inflicts the highest morbidity among children. Among the paediatric populace, severe exacerbations of asthma are a common reason behind patient consultations and hospitalizations. Oral corticosteroids are a primary component in the treatment of asthma exacerbations; however, there is controversy regarding how corticosteroids functions. METHODS: The present review will conduct a search on MEDLINE, EMBASE, Cochrane Library, China National Knowledge Infrastructure, and Chinese BioMedical Literature. The search will cover the databases from their beginning to May 2021. The search aims to identify all the randomized controlled studies on oral corticosteroids in treating children with asthma exacerbations. Two independent authors will choose studies, perform data extraction, and use an appropriate tool to assess the bias risk in the selected articles. Moreover, a sensitivity analysis will be performed to assess the robustness of the results. The RevMan (version 5.3) software will be employed to perform data synthesis and statistical analysis. RESULTS: This study will examine the efficiency and safeness of oral corticosteroid therapy to treat children with asthma exacerbations by pooling the results of individual studies. CONCLUSION: The findings of this study will provide vigorous evidence to judge whether oral corticosteroid therapy is an efficiency strategy to treat patients with asthmatic exacerbations. OSF REGISTRATION NUMBER: May 20, 2021.osf.io/3ghjt. (https://osf.io/3ghjt/).


Assuntos
Corticosteroides/administração & dosagem , Antiasmáticos/administração & dosagem , Asma/tratamento farmacológico , Administração Oral , Adolescente , Criança , Feminino , Humanos , Masculino , Metanálise como Assunto , Projetos de Pesquisa , Exacerbação dos Sintomas , Revisões Sistemáticas como Assunto , Resultado do Tratamento
8.
Medicine (Baltimore) ; 100(24): e26406, 2021 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-34128905

RESUMO

BACKGROUND: Respiratory distress syndrome (RDS) is a condition caused by a deficiency in pulmonary surfactant. Many interventions, including pulmonary surfactant, non-invasive respiratory support, and other supportive treatments have been used to prevent RDS. However, recent studies have focused on the continuous positive airway pressure as a significant potential agent for preventing RDS. However, its safety and effectiveness are yet to be assessed. To this end, the current study aims to perform to explore the safety and effectiveness of continuous positive airways in treating neonates with RDS. METHODS: We will conduct comprehensive literature searches on MEDLINE, Cochrane Library, EMBASE, Chinese National Knowledge Infrastructure, and Chinese BioMedical Literature from their inception to April 2021. The search aims to identify all the randomized controlled studies on continuous positive airway pressure in treating neonates with RDS. In addition, we aim to search the gray literature to establish any available potential studies. We will use 2 independent authors to determine study eligibility, extract data using the structured pro-forma table, analyze data, and utilize suitable tools in assessing the risk of bias in the selected studies. Accordingly, we will conduct all statistical analyses using RevMan 5.3 software. RESULTS: The current study aims to provide high-quality synthesis of existing evidence concerning the continuous positive airway pressure to treat neonates suffering from RDS. CONCLUSION: Our findings seek to provide evidence to establish whether continuous positive airway pressure can ascertain safety and effectiveness for neonates with RDS. ETHICS AND DISSEMINATION: The study will require ethical approval. OSF REGISTRATION NUMBER: May 20, 2021.osf.io/7nj8s. (https://osf.io/7nj8s/).


Assuntos
Pressão Positiva Contínua nas Vias Aéreas , Metanálise como Assunto , Síndrome do Desconforto Respiratório do Recém-Nascido/terapia , Revisões Sistemáticas como Assunto , Protocolos Clínicos , Pressão Positiva Contínua nas Vias Aéreas/efeitos adversos , Humanos , Recém-Nascido
9.
Medicine (Baltimore) ; 100(25): e26416, 2021 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-34160429

RESUMO

BACKGROUND: Cough variant asthma (CVA) is classified as a distinct form of asthma. As the primary or only symptom, cough is the leading cause for the most prevalent chronic cough among kids. The American College of Clinical Pharmacy, British Thoracic Society, and Chinese guidelines established for diagnosing and treating chronic cough in kids recommend inhaled corticosteroids, combined with leukotriene receptor antagonists when necessary. METHODS: We will conduct a comprehensive search in major databases using keywords to find studies related to the analysis of montelukast sodium and budesonide for treating CVA in kids. Two reviewers will independently assess the quality of the selected research articles and perform data extraction. Next, we will use the RevMan software (version: 5.3) to conduct the statistical analysis of the present study. RESULTS: This study will assess the efficacy and safeness of using montelukast sodium and budesonide to treat kids with CVA by pooling the results of individual studies. CONCLUSION: Our findings will provide vigorous evidence to judge whether montelukast sodium and budesonide therapy is an efficient form of therapy for CVA patients. ETHICS AND DISSEMINATION: Ethics approval is not needed for the present meta-analysis. OSF REGISTRATION NUMBER: May 17, 2021.osf.io/cuvjz (https://osf.io/cuvjz/).


Assuntos
Asma/tratamento farmacológico , Tosse/tratamento farmacológico , Glucocorticoides/administração & dosagem , Antagonistas de Leucotrienos/administração & dosagem , Acetatos/administração & dosagem , Acetatos/efeitos adversos , Administração por Inalação , Asma/diagnóstico , Asma/imunologia , Budesonida/administração & dosagem , Budesonida/efeitos adversos , Criança , Doença Crônica/tratamento farmacológico , Tosse/diagnóstico , Tosse/imunologia , Ciclopropanos/administração & dosagem , Ciclopropanos/efeitos adversos , Quimioterapia Combinada/efeitos adversos , Quimioterapia Combinada/métodos , Glucocorticoides/efeitos adversos , Humanos , Antagonistas de Leucotrienos/efeitos adversos , Metanálise como Assunto , Quinolinas/administração & dosagem , Quinolinas/efeitos adversos , Ensaios Clínicos Controlados Aleatórios como Assunto , Sulfetos/administração & dosagem , Sulfetos/efeitos adversos , Revisões Sistemáticas como Assunto , Resultado do Tratamento
10.
Huan Jing Ke Xue ; 32(12): 3694-8, 2011 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-22468542

RESUMO

The Si-doped TiO2 nanotubes photocatalysts was synthesized by anodic oxidation method, which used Na2SiF6/HF as an electrolyte, and was characterized by means of SEM, XRD, DRS and EDX. TiO2 nanotubes composed of anatase phase and rutile phase, and Si was highly dispersed on the wall of TiO2 nanotubes. The photocatalytic activity of the Si-doped TiO2 nanotubes was investigated for photocatalytic degradation of gaseous toluene. It was found that the photocatalytic activity of Si-doped TiO2 nanotubes, which prepared by 0.03 mol x L x (-1) Na2SiF6/HF and calcined at 400 degrees C for 1 h, was the highest. The conversion of toluene was 60% over the prepared Si doped TiO2 nanotubes under UV light, which was one times higher than that of pure TiO2 nanotubes.


Assuntos
Poluentes Atmosféricos/química , Nanotubos/química , Silício/química , Titânio/química , Compostos Orgânicos Voláteis/química , Poluentes Atmosféricos/isolamento & purificação , Catálise , Oxirredução , Processos Fotoquímicos , Tolueno/química , Tolueno/isolamento & purificação , Raios Ultravioleta , Compostos Orgânicos Voláteis/isolamento & purificação
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