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1.
Molecules ; 26(16)2021 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-34443343

RESUMO

Energy production and consumption without the use of fossil fuels are amongst the biggest challenges currently facing humankind and the scientific community. Huge efforts have been invested in creating technologies that enable closed carbon or carbon neutral fuel cycles, limiting CO2 emissions into the atmosphere. Formic acid/formate (FA) has attracted intense interest as a liquid fuel over the last half century, giving rise to a plethora of studies on catalysts for its efficient electrocatalytic oxidation for usage in fuel cells. However, new catalysts and catalytic systems are often difficult to compare because of the variability in conditions and catalyst parameters examined. In this review, we discuss the extensive literature on FA electrooxidation using platinum, palladium and non-platinum group metal-based catalysts, the conditions typically employed in formate electrooxidation and the main electrochemical parameters for the comparison of anodic electrocatalysts to be applied in a FA fuel cell. We focused on the electrocatalytic performance in terms of onset potential and peak current density obtained during cyclic voltammetry measurements and on catalyst stability. Moreover, we handpicked a list of the most relevant examples that can be used for benchmarking and referencing future developments in the field.

2.
J Am Chem Soc ; 141(36): 14306-14316, 2019 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-31426632

RESUMO

Selective separation of enantiomers is a substantial challenge for the pharmaceutical industry. Chromatography on chiral stationary phases is the standard method, but at a very high cost for industrial-scale purification due to the high cost of the chiral stationary phases. Typically, these materials are poorly robust, expensive to manufacture, and often too specific for a single desired substrate, lacking desirable versatility across different chiral analytes. Here, we disclose a porous, robust homochiral metal-organic framework (MOF), TAMOF-1, built from copper(II) and an affordable linker prepared from natural l-histidine. TAMOF-1 has shown to be able to separate a variety of model racemic mixtures, including drugs, in a wide range of solvents of different polarity, outperforming several commercial chiral columns for HPLC separations. Although not exploited in the present article, it is worthy to mention that the preparation of this new material is scalable to the multikilogram scale, opening unprecedented possibilities for low-energy chiral separation at the industrial scale.


Assuntos
Estruturas Metalorgânicas/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Cobre/química , Estruturas Metalorgânicas/química , Estrutura Molecular , Estereoisomerismo , Água/química
3.
J Shoulder Elbow Surg ; 28(7): 1395-1405, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30956143

RESUMO

HYPOTHESIS: Conservative treatment of isolated coronoid fractures and fracture-dislocations focused on soft-tissue healing can provide good clinical results in the majority of patients. Our aims were (1) to evaluate the outcome of a conservative treatment protocol designed for isolated coronoid fractures with or without associated elbow dislocations (ICFs) and (2) to characterize the fractures with a dedicated image analysis protocol. METHODS: Of 38 consecutive patients sustaining acute ICFs, 28 were treated nonsurgically after meeting specific inclusion criteria, prospectively followed up, and clinically evaluated at least 1 year after sustaining their injuries. All cases underwent elbow computed tomography scans with tri-plane and 3-dimensional reconstructions according to a specific protocol referenced to the proximal ulna. RESULTS: The study included 15 male and 13 female patients, with a mean follow-up period of 32 ± 14 months (range, 12-61 months). An associated dislocation was presented in 8 (29%). Mean extension and flexion were 2° ± 8° (range, -10° to 30°) and 139° ± 11° (range, 110°-155°), respectively. Mean pronation and supination were 74° ± 3° (range, 60°-75°) and 83° ± 9° (range, 40°-85°), respectively. Of the patients, 78% rated their elbow as being normal or nearly normal. The mean Mayo Elbow Performance Score was 95 ± 9 (range, 70-100). The mean Disabilities of the Arm, Shoulder and Hand score was 7 ± 13 (range, 0-57). The mean coronoid fracture height was 5.7 ± 1.2 mm (range, 3.7-7.9 mm). The mean percentage of coronoid height fractured was 33% ± 6% (range, 23%-43%). Mean fracture displacement was 2.7 ± 2 mm (range, 1-9 mm). Of the fractures, 23 (82%) were located at the anteromedial coronoid. CONCLUSION: An ICF with a perfectly reduced ulnohumeral joint, a competent sublime tubercle, and a fractured coronoid height up to 50% can be treated without surgery with excellent or good results in more than 90% of cases regardless of the location of the fracture in the coronoid or the type of soft tissue-associated disruptions.


Assuntos
Lesões no Cotovelo , Fratura-Luxação/terapia , Imobilização , Fraturas da Ulna/terapia , Adolescente , Adulto , Idoso , Moldes Cirúrgicos , Tratamento Conservador , Articulação do Cotovelo/diagnóstico por imagem , Articulação do Cotovelo/fisiopatologia , Feminino , Seguimentos , Fratura-Luxação/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Pronação , Amplitude de Movimento Articular , Supinação , Fraturas da Ulna/diagnóstico por imagem , Adulto Jovem
4.
Sensors (Basel) ; 14(10): 19200-28, 2014 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-25320907

RESUMO

The Internet of Things (IoT) enables the communication among smart objects promoting the pervasive presence around us of a variety of things or objects that are able to interact and cooperate jointly to reach common goals. IoT objects can obtain data from their context, such as the home, office, industry or body. These data can be combined to obtain new and more complex information applying data fusion processes. However, to apply data fusion algorithms in IoT environments, the full system must deal with distributed nodes, decentralized communication and support scalability and nodes dynamicity, among others restrictions. In this paper, a novel method to manage data acquisition and fusion based on a distributed service composition model is presented, improving the data treatment in IoT pervasive environments.

5.
ACS Appl Mater Interfaces ; 14(27): 30772-30785, 2022 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-35793095

RESUMO

Separation of volatile organic compounds is one of the most studied processes in industry. TAMOF-1 is a homochiral metal-organic framework with a crystalline network of interconnected ≈1 nm channels and has high thermal and chemical stability. Thanks to these features, it can resolve racemic mixtures of chiral drugs as a chiral stationary phase in chromatography. Interestingly, the particular shape and size of its channels, along with the presence of metallic centers and functional groups, allow establishing weak but significant interactions with guest molecules. This opens interesting possibilities not only to resolve racemates but also to separate other organic mixtures, such as saturated/unsaturated and/or linear/branched molecules. In search of these applications, we have studied the separation of volatile organic compounds in TAMOF-1. Monte Carlo simulations in the grand-canonical ensemble have been carried out to evaluate the separation of the selected molecules. Our results predict that TAMOF-1 is able to separate xylene isomers, hexane isomers, and benzene-cyclohexane mixtures. Experimental breakthrough analysis in the gas phase and also in the liquid phase confirms these predictions. Beds of TAMOF-1 are able to recognize the substitution in xylenes and the branching in hexanes, yielding excellent separation and reproducibility, thanks to the chemical and mechanical features of this material.

6.
Nat Commun ; 13(1): 4341, 2022 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-35896541

RESUMO

Earth-abundant electrocatalysts for the oxygen evolution reaction (OER) able to work in acidic working conditions are elusive. While many first-row transition metal oxides are competitive in alkaline media, most of them just dissolve or become inactive at high proton concentrations where hydrogen evolution is preferred. Only noble-metal catalysts, such as IrO2, are fast and stable enough in acidic media. Herein, we report the excellent activity and long-term stability of Co3O4-based anodes in 1 M H2SO4 (pH 0.1) when processed in a partially hydrophobic carbon-based protecting matrix. These Co3O4@C composites reliably drive O2 evolution a 10 mA cm-2 current density for >40 h without appearance of performance fatigue, successfully passing benchmarking protocols without incorporating noble metals. Our strategy opens an alternative venue towards fast, energy efficient acid-media water oxidation electrodes.

7.
Rev Sci Instrum ; 89(3): 035117, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29604727

RESUMO

In this study, a smartphone-based contact angle measurement instrument was developed. Compared with the traditional measurement instruments, this instrument has the advantage of simplicity, compact size, and portability. An automatic contact point detection algorithm was developed to allow the instrument to correctly detect the drop contact points. Two different contact angle calculation methods, Young-Laplace and polynomial fitting methods, were implemented in this instrument. The performance of this instrument was tested first with ideal synthetic drop profiles. It was shown that the accuracy of the new system with ideal synthetic drop profiles can reach 0.01% with both Young-Laplace and polynomial fitting methods. Conducting experiments to measure both static and dynamic (advancing and receding) contact angles with the developed instrument, we found that the smartphone-based instrument can provide accurate and practical measurement results as the traditional commercial instruments. The successful demonstration of use of a smartphone (mobile phone) to conduct contact angle measurement is a significant advancement in the field as it breaks the dominate mold of use of a computer and a bench bound setup for such systems since their appearance in 1980s.

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