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1.
J Am Chem Soc ; 146(21): 14369-14385, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38718351

RESUMO

Supercapacitors (SCs) are some of the most promising energy storage devices, but their low energy density is one main weakness. Over the decades, superior electrode materials and suitable electrolytes have been widely developed to enhance the energy storage ability of SCs. Particularly, constructing asymmetric supercapacitors (ASCs) can extend their electrochemical stable voltage windows (ESVWs) and thus achieve high energy density. However, only full utilization of the electrochemical stable potential windows (ESPWs) of both positive and negative electrodes can endow the ASC devices with a maximum ESVW by using a suitable mass-ratio between two electrodes (the mass-balancing). Nevertheless, insufficient attention is directed to mass-balancing, and even numerous misunderstandings and misuses have appeared. Therefore, in this Perspective, we focus on the mass-balancing: summarize theoretic basis of the mass-balancing, derive relevant relation equations, analyze and discuss the change trends of the specific capacitance and energy density of ASCs with mass-ratios, and finally recommend some guidelines for the normative implementation of the mass-balancing. Especially, the issues related to pseudocapacitive materials, hybrid devices, and different open circuit potentials (OCPs) of the positive and negative electrodes in the mass-balancing are included and emphasized. These analyses and guidelines can be conducive to understanding and performing mass-balancing for developing high-performance SCs.

2.
Langmuir ; 40(6): 3133-3141, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38307089

RESUMO

A Pickering emulsion is a natural microreactor for interfacial catalysis in which an emulsifier is critical. Recently, a metal-organic framework (MOF) has attracted attention to emulsify water-organic mixtures for constructing a Pickering emulsion. However, a few stimuli-responsive Pickering emulsions based on MOFs have been reported, and the MOF emulsifiers cannot be regenerated at room temperature. Herein, the Zr-MOF with a rodlike morphology is synthesized using ionic liquid as a modulator and then modified with n-(trimethoxysilylpropyl)imidazole (C3im) to prepare a series of functionalized Zr-MOFs (MOF-C3im). It is found that MOF-C3im is an excellent emulsifier to construct stable and CO2-responsive Pickering emulsions even at low content (>0.20 wt %). Notably, the emulsification and demulsification of the emulsions can be easily and reversibly switched by bubbling of CO2 and N2 alternatively at room temperature because CO2 and imidazole molecules anchored on the Zr-MOF underwent a reversible acid-base reaction, resulting in an obvious change in the wettability of the emulsifier. As a proof of concept, the reduction reactions of nitrobenzene have been successfully carried out in these Pickering emulsions, demonstrating the efficient integration as a microreactor for chemical reaction, product separation, and emulsifier recycling under ambient conditions. This strategy provides an innovative option to develop stimulus-responsive Pickering emulsions for sustainable chemical processes.

3.
Angew Chem Int Ed Engl ; 63(34): e202406855, 2024 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-38871653

RESUMO

In NH3 capture technologies, the desorption process is usually driven by high temperature and low pressure (such as 150-200 °C under vacuum), which accounts for intensive energy consumption and CO2 emission. Developing light responsive adsorbent is promising in this regard but remains a great challenge. Here, we for the first time designed and synthesized a light responsive azophenol-containing covalent organic framework (COF), COF-HNU38, to address this challenge. We found that at 25 °C and 1.0 bar, the cis -COF exhibited a NH3 uptake capacity of 7.7 mmol g-1 and a NH3/N2 selectivity of 158. In the adsorbed NH3, about 29.0 % could be removed by vis-light irradiated cis-trans isomerization at 25 °C, and the remaining NH3 might be released at 25 °C under vacuum. Almost no decrease in adsorption capacity was observed after eight adsorption-desorption cycles. As such, an efficient NH3 capture and low energy release strategy was established thanks to the multiple hydrogen bond interactions (which are strong in total but weak in individuals) between NH3 and the smart COF, as well as the increased polarity and number of hydrogen bond sites after the trans-cis isomerization.

4.
Int J Comput Assist Radiol Surg ; 19(5): 939-950, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38491244

RESUMO

PURPOSE: Pelvic X-ray (PXR) is widely utilized in clinical decision-making associated with the pelvis, the lower part of the trunk that supports and balances the trunk. In particular, PXR-based landmark detection facilitates downstream analysis and computer-assisted diagnosis and treatment of pelvic diseases. Although PXR has the advantages of low radiation and reduced cost compared to computed tomography (CT), it characterizes the 2D pelvis-tissue superposition of 3D structures, which may affect the accuracy of landmark detection in some cases. However, the superposition nature of PXR is implicitly handled by existing deep learning-based landmark detection methods, which mainly design the deep network structures for better detection performances. Explicit handling of the superposition nature of PXR is rarely done. METHODS: In this paper, we explicitly focus on the superposition of X-ray images. Specifically, we propose a pelvis extraction (PELE) module that consists of a decomposition network, a domain adaptation network, and an enhancement module, which utilizes 3D prior anatomical knowledge in CT to guide and well isolate the pelvis from PXR, thereby eliminating the influence of soft tissue for landmark detection. The extracted pelvis image, after enhancement, is then used for landmark detection. RESULTS: We conduct an extensive evaluation based on two public and one private dataset, totaling 850 PXRs. The experimental results show that the proposed PELE module significantly improves the accuracy of PXRs landmark detection and achieves state-of-the-art performances in several benchmark metrics. CONCLUSION: The design of PELE module can improve the accuracy of different pelvic landmark detection baselines, which we believe is obviously conducive to the positioning and inspection of clinical landmarks and critical structures, thus better serving downstream tasks. Our project has been open-sourced at https://github.com/ECNUACRush/PELEscores .


Assuntos
Pontos de Referência Anatômicos , Pelve , Tomografia Computadorizada por Raios X , Humanos , Pelve/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Imageamento Tridimensional/métodos , Aprendizado Profundo
5.
Rev. Assoc. Med. Bras. (1992, Impr.) ; 65(3): 355-360, Mar. 2019. graf
Artigo em Inglês | LILACS | ID: biblio-1003039

RESUMO

SUMMARY OBJECT: To explore the treatment effect of the anterior medial neurovascular interval approach to coronal shear fractures of the distal humerus. METHODS: This prospective study included two female patients who were 30-64 years old, with a mean age of 47 years. Fractures were caused by falling from a bicycle. The time between the injury and operation was 1-2 days, with a mean time interval of 1.5 days. Two patients with coronal shear fracture of the distal humerus were treated with open reduction and internal fixation using anterior neurovascular interval approach. RESULTS: There were no intraoperative and postoperative neurological and vascular complications or infections, and the fracture was united. At 12 months after the surgery, the patient returned to work without pain, and with a normal range of motion for elbow and forearm rotation. The X-rays revealed excellent fracture union, no signs of heterotopic ossification, and no traumatic arthritis. According to Mayo's evaluation standards for elbow function, a score of 100 is excellent. CONCLUSIONS: The application of the anterior neurovascular interval approach of the elbow in the treatment of shear fracture of the articular surface of the distal humerus, particularly the trochlea of the humerus, can reduce the stripping of the soft tissue.


RESUMO OBJETIVO: Explorar o efeito do tratamento com uma abordagem anterior do intervalo neurovascular médio para fraturas de cisalhamento coronal da porção distal do úmero. METODOLOGIA: Este estudo prospectivo incluiu duas pacientes do sexo feminino de 30-64 anos de idade, com idade média de 47 anos. As fraturas foram causadas por quedas de bicicleta. O tempo entre a lesão e a operação foi de 1-2 dias, com um intervalo de tempo médio de 1,5 dias. Duas pacientes com cisalhamento coronal da porção distal do úmero foram tratadas com redução aberta e fixação interna utilizando a abordagem anterior do intervalo neurovascular. RESULTADOS: Não houve complicações neurológicas e vasculares intra e pós-operatórias, nem complicações ou infecções, e a fratura foi unida. Após 12 meses da cirurgia, as pacientes retornaram ao trabalho sem dor e com uma amplitude normal de movimento de rotação do antebraço e cotovelo. Os raios-X revelaram excelente união das fraturas, sem sinais de ossificação heterotópica e sem artrite traumática. De acordo com as diretrizes da clínica Mayo para avaliação da função do cotovelo, uma pontuação de 100 é considerada excelente. CONCLUSÃO: A aplicação da abordagem anterior do intervalo neurovascular do cotovelo no tratamento de uma fratura de cisalhamento da superfície articular da porção distal do úmero, especificamente da tróclea do úmero, pode reduzir o desgaste do tecido mole.


Assuntos
Humanos , Feminino , Adulto , Procedimentos Cirúrgicos Vasculares/métodos , Procedimentos Neurocirúrgicos/métodos , Articulação do Cotovelo/cirurgia , Fixação Interna de Fraturas/métodos , Fraturas do Úmero/cirurgia , Úmero/lesões , Fatores de Tempo , Estudos Prospectivos , Reprodutibilidade dos Testes , Seguimentos , Resultado do Tratamento , Fraturas do Úmero/fisiopatologia , Úmero/fisiopatologia , Ilustração Médica , Pessoa de Meia-Idade
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