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1.
Nature ; 629(8010): 86-91, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38658763

RESUMO

Replacement of liquid electrolytes with polymer gel electrolytes is recognized as a general and effective way of solving safety problems and achieving high flexibility in wearable batteries1-6. However, the poor interface between polymer gel electrolyte and electrode, caused by insufficient wetting, produces much poorer electrochemical properties, especially during the deformation of the battery7-9. Here we report a strategy for designing channel structures in electrodes to incorporate polymer gel electrolytes and to form intimate and stable interfaces for high-performance wearable batteries. As a demonstration, multiple electrode fibres were rotated together to form aligned channels, while the surface of each electrode fibre was designed with networked channels. The monomer solution was effectively infiltrated first along the aligned channels and then into the networked channels. The monomers were then polymerized to produce a gel electrolyte and form intimate and stable interfaces with the electrodes. The resulting fibre lithium-ion battery (FLB) showed high electrochemical performances (for example, an energy density of about 128 Wh kg-1). This strategy also enabled the production of FLBs with a high rate of 3,600 m h-1 per winding unit. The continuous FLBs were woven into a 50 cm × 30 cm textile to provide an output capacity of 2,975 mAh. The FLB textiles worked safely under extreme conditions, such as temperatures of -40 °C and 80 °C and a vacuum of -0.08 MPa. The FLBs show promise for applications in firefighting and space exploration.

2.
Nature ; 597(7874): 57-63, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34471277

RESUMO

Fibre lithium-ion batteries are attractive as flexible power solutions because they can be woven into textiles, offering a convenient way to power future wearable electronics1-4. However, they are difficult to produce in lengths of more than a few centimetres, and longer fibres were thought to have higher internal resistances3,5 that compromised electrochemical performance6,7. Here we show that the internal resistance of such fibres has a hyperbolic cotangent function relationship with fibre length, where it first decreases before levelling off as length increases. Systematic studies confirm that this unexpected result is true for different fibre batteries. We are able to produce metres of high-performing fibre lithium-ion batteries through an optimized scalable industrial process. Our mass-produced fibre batteries have an energy density of 85.69 watt hour per kilogram (typical values8 are less than 1 watt hour per kilogram), based on the total weight of a lithium cobalt oxide/graphite full battery, including packaging. Its capacity retention reaches 90.5% after 500 charge-discharge cycles and 93% at 1C rate (compared with 0.1C rate capacity), which is comparable to commercial batteries such as pouch cells. Over 80 per cent capacity can be maintained after bending the fibre for 100,000 cycles. We show that fibre lithium-ion batteries woven into safe and washable textiles by industrial rapier loom can wirelessly charge a cell phone or power a health management jacket integrated with fibre sensors and a textile display.


Assuntos
Cobalto/química , Fontes de Energia Elétrica , Eletrônica , Lítio/química , Óxidos/química , Têxteis , Dispositivos Eletrônicos Vestíveis , Grafite/química , Humanos , Íons , Masculino , Tecnologia sem Fio
3.
Opt Express ; 31(23): 38688-38698, 2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-38017967

RESUMO

MXenes are a class of two-dimensional layered structure ternary metal carbide or/and nitride materials. Recently, the MXene V2CTx has demonstrated excellent long-term stability, strong saturable absorption, and fast optical-switching capability, used to generate Q-switched and ultrashort pulsed lasers. However, bound-state fiber lasers based on V2CTx have not been reported yet. In this study, V2CTx is combined with a D-shaped fiber to form a saturable absorber device, whose modulation depth is measured to be 1.6%. By inserting the saturable absorber into an Er-doped fiber laser, bound states with different soliton separation and munbers are successfully obtained. Additionally, bound states with a compound soliton structure, such as the (2 + 2)- and (2 + 1)-type, are also realized. Our findings show that V2CTx can be developed as an efficient ultrafast photonics candidate to further understand the complex nonlinear dynamics of bound-state pulses in fiber lasers.

4.
J Digit Imaging ; 36(3): 1262-1278, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36788195

RESUMO

Accurate registration of lung X-rays is an important task in medical image analysis. However, the conventional methods usually cost a lot in running time, and the existing deep learning methods are hard to deal with the large deformation caused by respiratory and cardiac motion. In this paper, we attempt to use deep learning methods to deal with large deformation and enable it to achieve the accuracy of conventional methods. We proposed the cascading affine and B-spline network (CABN), which consists of convolutional cross-stitch affine block (CCAB) and B-splines U-net-like block (BUB) for large lung motion. CCAB makes use of the convolutional cross-stitch model to learn global features among images. And BUB adopts the idea of cubic B-splines which is suitable for large deformation. We separately demonstrated CCAB, BUB, and CABN on two chest X-ray datasets. The experimental results indicate that our methods are highly competitive both in accuracy and runtime when compared to both other deep learning methods and iterative conventional approaches. Moreover, CCAB also can be used for the preprocessing of non-rigid registration methods, replacing affine in conventional methods.


Assuntos
Pulmão , Tomografia Computadorizada por Raios X , Humanos , Raios X , Radiografia , Tomografia Computadorizada por Raios X/métodos , Pulmão/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos
5.
Adv Mater ; 36(11): e2304876, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37543841

RESUMO

Photovoltaic devices represent an efficient electricity generation mode. Integrating them into textiles offers exciting opportunities for smart electronic textiles-with the ultimate goal of supplying power for wearable technology-which is poised to change how electronic devices are designed. Many human activities occur indoors, so realizing indoor photovoltaic fibers (IPVFs) that can be woven into textiles to power wearables is critical, although currently unavailable. Here, a dye-sensitized IPVF is constructed by incorporating titanium dioxide nanoparticles into aligned nanotubes to produce close contact and stable interfaces among active layers on a curved fiber substrate, thus presenting efficient charge transport and low charge recombination in the photoanode. With the combination of highly conductive core-sheath Ti/carbon nanotube fiber as a counter electrode, the IPVF shows a certified power conversion efficiency of 25.53% under 1500 lux illuminance. Its performance variation is below 5% after bending, twisting, or pressing for 1000 cycles. These IPVFs are further integrated with fiber batteries as self-charging power textiles, which are demonstrated to effectively supply electricity for wearables, solving the power supply problem in this important direction.

6.
Food Sci Nutr ; 8(7): 3673-3681, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32724630

RESUMO

The fate of nanoparticles in the ecological chain of agriculture has been concerned as their potential pollution and biological effect to humans with rapid development and massive emission of nanomaterials. Here, we found that two rice cultivars (Oryza sativa L) have different heavy metal accumulation results in the roots and shoots after 15 days growth. Two rice cultivars (Oryza sativa L), grown in soil containing magnetite (Fe3O4@NH2) nanoparticles and heavy metal simultaneous, showed less Pb uptake in the roots and shoots, compared with that without Fe3O4@NH2 added. The shape and magnetic properties of Fe3O4@NH2 have no obvious change; however, the transmission electron microscope (TEM) results showed the shell of Fe3O4@NH2 could be broken in the process of interaction with soil. These results suggested that magnetite nanoparticles, such as Fe3O4@NH2, could potentially be used as the recyclable heavy metal fixation materials for alleviating heavy metal poisoning to plant.

7.
Artigo em Inglês | MEDLINE | ID: mdl-33322674

RESUMO

Health-related quality of life (HRQOL) of caregivers of children with disabilities (CWD) is important for both children's rehabilitation and caregivers' life, but the corresponding attention is far from enough in mainland China. Thus, we investigated the HRQOL of 170 caregivers and related factors in Shanghai. The 12-item Short Form Health Survey (SF-12) was used to measure HRQOL. The potential factors were collected, including child characteristics, caregiver characteristics, and environmental factors. Univariate analysis and multiple linear regression were performed to identify the key factors that could be intervened. Compared with the general population, caregivers of CWD had a slightly higher score on the physical component summary (PCS, 52.57 ± 8.41), but the score of mental component summary (MCS, 31.58 ± 7.72) was extremely low. Caregiver's illness condition, family size, and household income were significant factors of physical HRQOL. Caregivers with illness and caregivers living in an extended family were associated with higher mental HRQOL. Whereas these two factors had opposite effects on physical HRQOL. This finding indicated poor mental HRQOL among caregivers of CWD in Shanghai and thus requiring urgent attention and intervention. Improving physical fitness, maintaining family integration, and providing financial support should be considered when developing intervention for this population.


Assuntos
Cuidadores , Crianças com Deficiência , Qualidade de Vida , Adolescente , Criança , Pré-Escolar , China , Estudos Transversais , Feminino , Nível de Saúde , Humanos , Lactente , Masculino , Inquéritos e Questionários
8.
Front Genet ; 8: 113, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28919908

RESUMO

The inactivation of ribosomal protein S6 kinase 1 (S6K1) recapitulates aspects of caloric restriction and mTORC1 inhibition to achieve prolonged longevity in invertebrate and mouse models. In addition to delaying normative aging, inhibition of mTORC1 extends the shortened lifespan of yeast, fly, and mouse models with severe mitochondrial disease. Here we tested whether disruption of S6K1 can recapitulate the beneficial effects of mTORC1 inhibition in the Ndufs4 knockout (NKO) mouse model of Leigh Syndrome caused by Complex I deficiency. These NKO mice develop profound neurodegeneration resulting in brain lesions and death around 50-60 days of age. Our results show that liver-specific, as well as whole body, S6K1 deletion modestly prolongs survival and delays onset of neurological symptoms in NKO mice. In contrast, we observed no survival benefit in NKO mice specifically disrupted for S6K1 in neurons or adipocytes. Body weight was reduced in WT mice upon disruption of S6K1 in adipocytes or whole body, but not altered when S6K1 was disrupted only in neurons or liver. Taken together, these data indicate that decreased S6K1 activity in liver is sufficient to delay the neurological and survival defects caused by deficiency of Complex I and suggest that mTOR signaling can modulate mitochondrial disease and metabolism via cell non-autonomous mechanisms.

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