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1.
Sci Bull (Beijing) ; 68(5): 516-527, 2023 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-36841731

RESUMEN

Solid oxide electrochemical cells (SOCs) hold potential as a critical component in the future landscape of renewable energy storage and conversion systems. However, the commercialization of SOCs still requires further breakthroughs in new material development and engineering designs to achieve high performance and durability. In this study, a data-driven powder-to-power framework has been presented, fully digitizing the morphology evolution of heterogeneous electrodes from fabrication to long-term operation. This framework enables accurate performance prediction over the full life cycle. The intrinsic correlation between microstructural parameters and electrode durability is elucidated through parameter analysis. Rational control of the ion-conducting phase volume fraction can effectively suppress Ni coarsening and mitigate the excessive ohmic loss caused by Ni migration. The initial and degraded electrode performances are attributed to the interplay of multiple parameters. A practical optimization strategy to enhance the initial performance and durability of the electrode is proposed through the construction of the surrogate model and the application of the optimization algorithm. The optimal electrode parameters are determined to accommodate various maximum operation time requirements. By implementing the data-driven powder-to-power framework, it is possible to reduce the degradation rate of Ni-based electrodes from 2.132% to 0.703% kh-1 with a required maximum operation time of over 50,000 h.

2.
Nanoscale Horiz ; 7(3): 255-266, 2022 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-35037684

RESUMEN

An optimum balance between performance and Pt loading is critically important for the commercialization of proton exchange membrane (PEM) fuel cells. This research aims to investigate the interlink among Pt loading, reactive transport, and performance. An advanced pore-scale model is developed to describe the coupled reactive transport in the catalyst layer (CL) with the reactant gas, protons, and electrons all considered. The CL microstructure is stochastically reconstructed as a computational domain, and the physicochemical phenomena inside CLs are resolved by a multi-component lattice Boltzmann (LB) model. The results show that the electronic potential drop is not sensitive to Pt loading, while the ionic potential drop is much higher. The distributions of local overpotential and the reaction rate are similar with peak values near the membrane, indicating the importance of proton conduction. A high Pt loading could decrease the local transport loss for a shorter path to catalyst sites, but increases the overall transport resistance for a thicker structure. Although a larger electrochemical surface area (ECSA) is provided under a high Pt loading, a low Pt loading (0.1 mg cm-2) is suggested for high current conditions (2 A cm-2) where the transport loss is the main factor restricting the performance.

3.
ACS Appl Mater Interfaces ; 14(3): 3849-3863, 2022 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-35019259

RESUMEN

Nitric oxide (NO) is an endogenous gasotransmitter regulating alternative physiological processes in the cardiovascular system. To achieve translational application of NO, continued efforts are made on the development of orally active NO prodrugs for long-term treatment of chronic cardiovascular diseases. Herein, immobilization of NO-delivery [Fe2(µ-SCH2CH2COOH)2(NO)4] (DNIC-2) onto MIL-88B, a metal-organic framework (MOF) consisting of biocompatible Fe3+ and 1,4-benzenedicarboxylate (BDC), was performed to prepare a DNIC@MOF microrod for enhanced oral delivery of NO. In simulated gastric fluid, protonation of the BDC linker in DNIC@MOF initiates its transformation into a DNIC@tMOF microrod, which consisted of DNIC-2 well dispersed and confined within the BDC-based framework. Moreover, subsequent deprotonation of the BDC-based framework in DNIC@tMOF under simulated intestinal conditions promotes the release of DNIC-2 and NO. Of importance, this discovery of transformer-like DNIC@MOF provides a parallel insight into its stepwise transformation into DNIC@tMOF in the stomach followed by subsequent conversion into molecular DNIC-2 in the small intestine and release of NO in the bloodstream of mice. In comparison with acid-sensitive DNIC-2, oral administration of DNIC@MOF results in a 2.2-fold increase in the oral bioavailability of NO to 65.7% in mice and an effective reduction of systolic blood pressure (SBP) to a ΔSBP of 60.9 ± 4.7 mmHg in spontaneously hypertensive rats for 12 h.


Asunto(s)
Materiales Biocompatibles/farmacología , Estructuras Metalorgánicas/farmacología , Óxido Nítrico/química , Profármacos/farmacología , Administración Oral , Animales , Materiales Biocompatibles/administración & dosificación , Presión Sanguínea/efectos de los fármacos , Electrodos , Concentración de Iones de Hidrógeno , Ensayo de Materiales , Estructuras Metalorgánicas/administración & dosificación , Ratones , Óxido Nítrico/administración & dosificación , Tamaño de la Partícula , Profármacos/química , Propiedades de Superficie
4.
JACS Au ; 1(7): 998-1013, 2021 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-34467346

RESUMEN

Nitric oxide (NO), a pro-neurogenic and antineuroinflammatory gasotransmitter, features the potential to develop a translational medicine against neuropathological conditions. Despite the extensive efforts made on the controlled delivery of therapeutic NO, however, an orally active NO prodrug for a treatment of chronic neuropathy was not reported yet. Inspired by the natural dinitrosyl iron unit (DNIU) [Fe(NO)2], in this study, a reversible and dynamic interaction between the biomimetic [(NO)2Fe(µ-SCH2CH2OH)2Fe(NO)2] (DNIC-1) and serum albumin (or gastrointestinal mucin) was explored to discover endogenous proteins as a vehicle for an oral delivery of NO to the brain after an oral administration of DNIC-1. On the basis of the in vitro and in vivo study, a rapid binding of DNIC-1 toward gastrointestinal mucin yielding the mucin-bound dinitrosyl iron complex (DNIC) discovers the mucoadhesive nature of DNIC-1. A reversible interconversion between mucin-bound DNIC and DNIC-1 facilitates the mucus-penetrating migration of DNIC-1 shielded in the gastrointestinal tract of the stomach and small intestine. Moreover, the NO-release reactivity of DNIC-1 induces the transient opening of the cellular tight junction and enhances its paracellular permeability across the intestinal epithelial barrier. During circulation in the bloodstream, a stoichiometric binding of DNIC-1 to the serum albumin, as another endogenous protein vehicle, stabilizes the DNIU [Fe(NO)2] for a subsequent transfer into the brain. With aging mice under a Western diet as a disease model for metabolic syndrome and cognitive impairment, an oral administration of DNIC-1 in a daily manner for 16 weeks activates the hippocampal neurogenesis and ameliorates the impaired cognitive ability. Taken together, these findings disclose the synergy between biomimetic DNIC-1 and endogenous protein vehicles for an oral delivery of therapeutic NO to the brain against chronic neuropathy.

5.
Cyberpsychol Behav Soc Netw ; 13(4): 473-5, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20649447

RESUMEN

Abstract This study examines the use of the virtual enterprise network supplier supply-chain model of business behavior in creating synergies of cooperation. To explore virtual network behavior, it evaluates 60 samples, taken from of a few supply chains, and 17 items meeting certain behavioral criteria. Such an analysis may help to reduce costs and processing time effectively, as well as promote effective communication. Furthermore, the study of behavior in this electronic setting is a reliable and useful assessment method.


Asunto(s)
Comercio , Redes de Comunicación de Computadores , Simulación por Computador , Comportamiento del Consumidor , Conducta Cooperativa , Análisis de Varianza , Humanos , Modelos Económicos , Taiwán
6.
Waste Manag ; 28(8): 1386-94, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-17689065

RESUMEN

While Taiwanese hospitals dispose of large amounts of medical waste to ensure sanitation and personal hygiene, doing so inefficiently creates potential environmental hazards and increases operational expenses. However, hospitals lack objective criteria to select the most appropriate waste disposal firm and evaluate its performance, instead relying on their own subjective judgment and previous experiences. Therefore, this work presents an analytic hierarchy process (AHP) method to objectively select medical waste disposal firms based on the results of interviews with experts in the field, thus reducing overhead costs and enhancing medical waste management. An appropriate weight criterion based on AHP is derived to assess the effectiveness of medical waste disposal firms. The proposed AHP-based method offers a more efficient and precise means of selecting medical waste firms than subjective assessment methods do, thus reducing the potential risks for hospitals. Analysis results indicate that the medical sector selects the most appropriate infectious medical waste disposal firm based on the following rank: matching degree, contractor's qualifications, contractor's service capability, contractor's equipment and economic factors. By providing hospitals with an effective means of evaluating medical waste disposal firms, the proposed AHP method can reduce overhead costs and enable medical waste management to understand the market demand in the health sector. Moreover, performed through use of Expert Choice software, sensitivity analysis can survey the criterion weight of the degree of influence with an alternative hierarchy.


Asunto(s)
Contaminación Ambiental/prevención & control , Eliminación de Residuos Sanitarios/métodos , Administración de Residuos/métodos , Algoritmos , Conservación de los Recursos Naturales , Recolección de Datos , Ambiente , Contaminantes Ambientales , Contaminación Ambiental/análisis , Residuos Peligrosos , Humanos , Residuos Sanitarios , Modelos Estadísticos , Modelos Teóricos , Sensibilidad y Especificidad
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