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1.
Inorg Chem ; 63(27): 12681-12689, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38922608

RESUMO

The oxygen reduction reaction (ORR) plays a vital role in many next-generation electrochemical energy conversion and storage devices, motivating the search for low-cost ORR electrocatalysts possessing high activity and excellent durability. In this work, we demonstrate that iron-cobalt phosphide (FeCoP) nanoparticles encapsulated in a N-doped carbon framework (FeCoP@NC) represent a very promising catalyst for the ORR in alkaline media. The core-shell structured FeCoP@NC catalyst offered outstanding ORR activity with a half-wave potential (E1/2) of 0.86 V vs reversible hydrogen electrode (RHE) and excellent stability in a 0.1 M KOH electrolyte, outperforming commercial Pt/C and many recently reported noble-metal-free ORR electrocatalysts. The superiority of FeCoP@NC as an ORR electrocatalyst relative to Pt/C was further verified in prototype zinc-air batteries (ZABs), with the aqueous and flexible ZABs prepared using FeCoP@NC offering excellent stability, impressive open circuit voltages (1.56 and 1.44 V, respectively), and high maximum power densities (183.5 and 69.7 mW cm-2, respectively). Density functional theory calculations revealed that encapsulating FeCoP nanoparticles in N-doped carbon shells resulted in favorable electron penetration effects, which synergistically regulated the adsorption/desorption of ORR intermediates for optimal ORR performance while also boosting the electronic conductivity. Our findings offer valuable new insights for rational design of transition metal phosphide-based catalysts for the ORR and other electrochemical applications.

3.
Artigo em Inglês | MEDLINE | ID: mdl-35627718

RESUMO

The new wave of reform of collective forestland tenure (NRCFT) in China is considered an important policy for achieving sustainable management of forest resources. The purpose of this study is to investigate the influence of NRCFT on forest fragmentation in the Beijing-Tianjin-Hebei region of China based on a fixed-effects model. The forest fragmentation was analyzed based on the remote sensing images of Landsat and landscape pattern indices in the Beijing-Tianjin-Hebei region from 2000 to 2018. The results showed that (1) The NRCFT has significantly contributed to reducing forest fragmentation. (2) The effect of economic growth on forest fragmentation showed an inverted U-shape. (3) The implementation of the Grain for Green Program (GGP) and the transformation of rural energy consumption significantly reduce the degree of forest fragmentation. This study has crucial implications for formulating policies, achieving good forest governance, and reducing forest fragmentation.


Assuntos
Desenvolvimento Econômico , Florestas , Pequim , China
4.
Med Sci Monit ; 27: e928804, 2021 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-33414360

RESUMO

BACKGROUND This study aimed to assess the correlation between the variability of the end-inspiratory and end-expiratory blood flow waveform and fluid responsiveness (FR) in traumatic shock patients who underwent mechanical ventilation by evaluating peripheral arterial blood flow parameters. MATERIAL AND METHODS A cohort of 60 patients with traumatic shock requiring mechanical ventilation-controlled breathing received ultrasound examinations to assess the velocity of carotid artery (CA), femoral artery (FA) and brachial artery (BA). A rehydration test was performed in which of 250 mL of 0.9% saline was administered within 30 min between the first and second measurement of cardiac output by echocardiography. Then, all patients were divided into 2 groups, a responsive group (FR+) and a non-responsive group (FR-). The velocity of end-inspiratory and end-expiratory peripheral arterial blood flow of all patients was ultrasonically measured, and the variability were measured between end-inspiratory and end-expiratory. RESULTS The changes in the end-inspiratory and end-expiratory carotid artery blood flow velocity waveforms of the FR+ groups were significantly different from those of the FR- group (P<0.001). A statistically significant difference in ΔVmax (CA), ΔVmax (BA), and ΔVmax (FA) between these 2 groups was found (all P<0.001). The ROC curve showed that DVmax (CA) and ΔVmax (BA) were more sensitive values to predict FR compared to ΔVmax (FA). The sensitivity of ΔVmax (CA), ΔVmax (FA), and ΔVmax (BA) was 70.0%, 86.7%, and 93.3%, respectively. CONCLUSIONS The study showed that periodic velocity waveform changes in the end-inspiratory and end-expiratory peripheral arterial blood flow can be used for quick assessment of fluid responsiveness.


Assuntos
Velocidade do Fluxo Sanguíneo , Hidratação/métodos , Respiração , Choque Traumático/diagnóstico , Adulto , Idoso , Artérias Carótidas/diagnóstico por imagem , Velocidade da Onda de Pulso Carótido-Femoral/métodos , Feminino , Artéria Femoral/diagnóstico por imagem , Hidratação/normas , Humanos , Masculino , Pessoa de Meia-Idade , Respiração Artificial/métodos , Choque Traumático/diagnóstico por imagem , Choque Traumático/terapia , Ultrassonografia/métodos
5.
Environ Manage ; 62(1): 58-69, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29297091

RESUMO

Forest landscape restoration is emerging as an effective approach to restore degraded forests for the provision of ecosystem services and to minimize trade-offs between conservation and rural livelihoods. Policy and institutional innovations in China illustrate the governance transformation of forest landscape restoration from state-controlled to polycentric governance. Based on a case study of the Ecological Forest Purchase Program in Yong'an municipality, China's Fujian Province, this paper explores how such forest governance transformation has evolved and how it has shaped the outcomes of forest landscape restoration in terms of multi-dimensionality and actor configurations. Our analysis indicates that accommodating the participation of multiple actors and market-based instruments facilitate a smoother transition from state-centered to polycentric governance in forest landscape restoration. Governance transitions for forest landscape restoration must overcome a number of challenges including ensurance of a formal participation forum, fair participation, and a sustainable legislative and financial system to enhance long-term effectiveness.


Assuntos
Política Ambiental/tendências , Recuperação e Remediação Ambiental/métodos , Agricultura Florestal/organização & administração , Florestas , Regulamentação Governamental , China , Ecologia , Política Ambiental/economia , Política Ambiental/legislação & jurisprudência , Recuperação e Remediação Ambiental/economia , Recuperação e Remediação Ambiental/legislação & jurisprudência , Agricultura Florestal/economia , Agricultura Florestal/legislação & jurisprudência , Humanos
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