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1.
Adv Mater ; 36(25): e2400656, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38519417

RESUMO

The advanced lithium-ion batteries that can tolerate zero-volt storage (ZVS) are in high demand for implantable medical devices and spacecraft. However, ZVS can raise the anode potential, leading to Cu current collector dissolution and solid-electrolyte interphase (SEI) degradation, especially at 37 °C. In this contribution, by quantitatively regulating the dosage of Li6CoO4 cathode additives, controllable potential of the working anode under abusive-discharge conditions is demonstrated. The addition of Li6CoO4 keeps zero-crossing potential (ZCP) and the potential of ZVS below 2.0 V (vs Li/Li+) for LiCoO2|mesocarbon microbead cells at 37 °C. The capacity retention ratio (CRR) increases from 69.1% and 35.9% to 98.6% and 90.8% after 10 and 20 days of ZVS, respectively. The Cu dissolution and SEI degradation are effectively suppressed, while the over-lithiated cathode exhibits high reversible capacity after ZVS. The limiting conditions of long-term ZVS are further explored and a corresponding guide map is designed. When quantitatively regulating ZCP and the potential in ZVS, Cu dissolution, SEI degradation, and irreversible conversion of the cathode constitute the limiting conditions. This contribution designs the most reasonable potential range for ZVS protection at 37 °C, and realizes the best CRR record through precise potential regulation for the first time.

2.
Opt Express ; 31(8): 12232-12248, 2023 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-37157387

RESUMO

This paper presents a maskless lithography system that can perform three-dimensional (3D) ultraviolet (UV) patterning on a photoresist (PR) layer. After PR developing processes, patterned 3D PR microstructures over a large area are obtained. This maskless lithography system utilizes an UV light source, a digital micromirror device (DMD), and an image projection lens to project a digital UV image on the PR layer. The projected UV image is then mechanically scanned over the PR layer. An UV patterning scheme based on the idea of obliquely scanning and step strobe lighting (OS3L) is developed to precisely control the spatial distribution of projected UV dose, such that desired 3D PR microstructures can be obtained after PR development. Two types of concave microstructures with truncated conical and nuzzle-shaped cross-sectional profiles are experimentally obtained over a patterning area of 160 ×115 mm2. These patterned microstructures are then used for replicating nickel molds and for mass-production of light-guiding plates used in back-lighting and display industry. Potential improvements and advancements of the proposed 3D maskless lithography technique for future applications will be addressed.

3.
Photodiagnosis Photodyn Ther ; 38: 102839, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35367615

RESUMO

BACKGROUND: Although 5-aminolevulinic acid photodynamic therapy (ALA-PDT) has been extensively used to treat various skin diseases, application for the treatment of cutaneous infection caused by Mycobacterium marinum (M. marinum), especially drug-resistant M. marinum, is unclear. OBJECTIVES: We evaluated the efficacy of ALA-PDT on M. marinum in a mouse infection model and tested its killing effect on M. marinum in vitro. We also investigated the clinical effect of ALA-PDT on cutaneous granuloma caused by drug-resistant M. marinum. MATERIALS AND METHODS: A total of 9 M. marinum strains isolated from patients were tested for anti-mycobacterial susceptibility. The effects of ALA-PDT on M. marinum in vitro and in mice model were investigated. Therapeutic efficacy was further assessed in two patients with cutaneous granuloma caused by drug- resistant M. marinum. RESULTS: We demonstrated that ALA-PDT directly killed M. marinum in vitro. The cutaneous lesions on mouse paws caused by M. marinum were fully recovered 4 weeks after the ALA-PDT treatment. ALA-PDT was also effective in two patients with cutaneous infection caused by drug-resistant M. marinum. The level of intracellular ROS in M. marinum treated with ALA-PDT was significantly higher than that of M. marinum alone. CONCLUSIONS: The results suggest that ALA-PDT is effective in treating M. marinum cutaneous infections by releasing more reactive oxygen species to kill M. marinum directly, and these effects are independent of systemic immune responses. The data highlights that ALA-PDT is a promising therapeutic choice for treatment of M. marinum cutaneous infections, especially drug-resistant M. marinum infections.


Assuntos
Mycobacterium marinum , Fotoquimioterapia , Neoplasias Cutâneas , Ácido Aminolevulínico/farmacologia , Ácido Aminolevulínico/uso terapêutico , Animais , Granuloma/tratamento farmacológico , Humanos , Camundongos , Infecções por Mycobacterium não Tuberculosas , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Neoplasias Cutâneas/tratamento farmacológico
4.
J Microsc ; 286(2): 85-91, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34725826

RESUMO

Burning of clinker is the most influencing step of cement quality during the production process. Appropriate characterisation for quality control and decision-making is therefore the critical point to maintain a stable production but also for the development of alternative cements. Scanning electron microscopy (SEM) in combination with energy dispersive X-ray spectroscopy (EDX) delivers spatially resolved phase and chemical information for cement clinker. This data can be used to quantify phase fractions and chemical composition of identified phases. The contribution aims to provide an overview of phase fraction quantification by semi-automatic phase segmentation using high-resolution backscattered electron (BSE) images and lower-resolved EDX element maps. Therefore, a tool for image analysis was developed that uses state-of-the-art algorithms for pixel-wise image segmentation and labelling in combination with a decision tree that allows searching for specific clinker phases. Results show that this tool can be applied to segment sub-micron scale clinker phases and to get a quantification of all phase fractions. In addition, statistical evaluation of the data is implemented within the tool to reveal whether the imaged area is representative for all clinker phases.


Assuntos
Materiais de Construção , Elétrons , Materiais de Construção/análise , Microscopia Eletrônica de Varredura , Espectrometria por Raios X/métodos , Fluxo de Trabalho
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