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1.
ACS Nano ; 18(20): 12820-12829, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38722145

RESUMEN

Developing highly efficient catalysts, characterized by controllable pore architecture and effective utilization of active sites, is paramount in addressing the shuttle effect and sluggish redox kinetics of lithium polysulfides (LiPSs) in lithium-sulfur batteries (LSBs), which, however, remains a formidable challenge. In this study, a hierarchical porous catalytic metal-organic framework (HPC-MOF) with both appropriate porosity and abundant exposed catalytic sites is achieved through time-controlled precise pore engineering. It is revealed that the evolution of the porous structure and catalytic site density is time-dependent during the etching processes. The moderately etched HPC-MOF-M attains heterogeneous pores at various scales, where large apertures ensure fast mass transfer and micropores inherit high-density catalytic sites, enhancing utilization and catalytic kinetics at internal catalytic sites. Capitalizing on these advantages, LSB incorporating the HPC-MOF-M interlayer demonstrates a 164.6% improvement in discharge capability and an 83.3% lower decay rate over long-term cycling at 1.0C. Even under high sulfur loading of 7.1 mg cm-2 and lean electrolyte conditions, the LSB exhibits stable cycling for over 100 cycles. This work highlights the significance of balancing the relationship between mass transfer and catalytic sites through precise chemical regulation of the porous structure in catalytic MOFs, which are anticipated to inspire the development of advanced catalysts for LSBs.

2.
Adv Mater ; : e2401284, 2024 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-38574258

RESUMEN

The development of solid-state electrolytes (SSEs) with outstanding comprehensive performance is currently a critical challenge for achieving high energy density and safer solid-state batteries (SSBs). In this study, a strategy of nano-confined in situ solidification is proposed to create a novel category of molten guest-mediated metal-organic frameworks, named MGM-MOFs. By embedding the newly developed molten crystalline organic electrolyte (ML20) into the nanocages of anionic MOF-OH, MGM-MOF-OH, characterized by multi-modal supramolecular interaction sites and continuous negative electrostatic environments within nano-channels, is achieved. These nanochannels promote ion transport through the successive hopping of Li+ between neighbored negative electrostatic environments and suppress anion movement through the chemical constraint of the hydroxyl-functionalized pore wall. This results in remarkable Li+ conductivity of 7.1 × 10-4 S cm-1 and high Li+ transference number of 0.81. Leveraging these advantages, the SSBs assembled with MGM-MOF-OH exhibit impressive cycle stability and a high specific energy density of 410.5 Wh kganode + cathode + electrolyte -1 under constrained conditions and various working temperatures. Unlike flammable traditional MOFs, MGM-MOF-OH demonstrates high robustness under various harsh conditions, including ignition, high voltage, and extended to humidity.

3.
Angew Chem Int Ed Engl ; 63(8): e202318859, 2024 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-38179841

RESUMEN

The development of highly efficient catalysts to address the shuttle effect and sluggish redox kinetics of lithium polysulfides (LiPSs) in lithium-sulfur batteries (LSBs) remains a formidable challenge. In this study, a series of multi-site catalytic metal-organic frameworks (MSC-MOFs) were elaborated through multimodal molecular engineering to regulate both the reactant diffusion and catalysis processes. MSC-MOFs were crafted with nanocages featuring collaborative specific adsorption/catalytic interfaces formed by exposed mixed-valence metal sites and surrounding adsorption sites. This design facilitates internal preconcentration, a coadsorption mechanism, and continuous efficient catalytic conversion toward polysulfides concurrently. Leveraging these attributes, LSBs with an MSC-MOF-Ti catalytic interlayer demonstrated a 62 % improvement in discharge capacity and cycling stability. This resulted in achieving a high areal capacity (11.57 mAh cm-2 ) at a high sulfur loading (9.32 mg cm-2 ) under lean electrolyte conditions, along with a pouch cell exhibiting an ultra-high gravimetric energy density of 350.8 Wh kg-1 . Lastly, this work introduces a universal strategy for the development of a new class of efficient catalytic MOFs, promoting SRR and suppressing the shuttle effect at the molecular level. The findings shed light on the design of advanced porous catalytic materials for application in high-energy LSBs.

4.
Front Public Health ; 11: 1128334, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37521967

RESUMEN

Background: Population knowledge and attitudes toward obstructive sleep apnea (OSA) syndrome are critical to public health initiatives to overcome the disease. Healthcare education is an appropriate approach to expediting the process to build active medical practice models in the public. Objective: This study aimed to assess the level of knowledge, attitude, and practice (KAP) regarding OSA and healthcare education demand among the Chinese general population. Methods: A cross-sectional survey was performed online via Wenjuanxing in China between 8 February and 8 March 2022, using a 34-item questionnaire designed and reviewed by multidisciplinary experts. Results: This study enrolled 1507 respondents, aged 18 to 68, with a city-to-countryside ratio of approximately 2:1. Four-fifths of respondents reported that they had children (n = 1237), and mothers accounted for 57.7%. If they or their children had symptoms of OSA, nearly nine in 10 respondents would undertake positive medical practices, especially parents. A total of 89.4% of the respondents reported a desire to receive healthcare education through the new multimedia approach, and most were concerned about the etiology of OSA. Conclusion: The current study indicated that even the higher educated and urban populations in China had insufficient knowledge about positive attitudes toward and practices regarding OSA, indicating an urgent demand for healthcare education. A special emphasis should be placed on appropriating population demand for healthcare education and promoting the benefits of active medical practice models in sleep medicine.


Asunto(s)
Conocimientos, Actitudes y Práctica en Salud , Apnea Obstructiva del Sueño , Femenino , Humanos , Estudios Transversales , Pueblos del Este de Asia , Escolaridad , Apnea Obstructiva del Sueño/terapia , Apnea Obstructiva del Sueño/diagnóstico , Masculino , Adolescente , Adulto Joven , Adulto , Persona de Mediana Edad , Anciano
5.
J Voice ; 2023 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-37380583

RESUMEN

PURPOSE: This study aimed to investigate Chinese parents' perceptions of pediatric voice disorders to determine their level of health literacy and knowledge gaps to understand the determinants of initiating voice therapy for children with dysphonia. METHOD: A cross-sectional survey was conducted in three voice clinics in Chengdu, China, from October 1, 2021, to October 1, 2022. Impairment of children's quality of life as perceived by parents was assessed using the pediatric Voice-Related Quality-of-Life (pVRQOL) scale. RESULTS: Overall, 206 parents whose children were recommended voice therapy were recruited (Mean ± SD age, 35.0 ± 4.62 years; male/female = 1:3). When otolaryngologists recommended that their children with dysphonia initiate voice therapy, most participants had positive responses (n = 176, 85.4%). The mean pVRQOL score was 40.8 in the accept group and 37.6 in the reject group (difference, 1.7; 95% CI, -4.98 1.69). Participants who had a more influential work status, had an only-child, had children with shorter-term voice symptoms, and visited specialized hospitals were more likely to have negative practices related to children's voice therapy (P < 0.05). CONCLUSIONS: This study represents an important first step in understanding Chinese parents' perceptions of and motivations for initiating voice therapy for their children with dysphonia. Initiation of treatment as recommended in pediatric populations depends on multiple factors, such as the duration of voice symptoms, family structure, and hospital type. It is imperative to promote public health care education on voice therapy among parents, as health care literacy is the primary driving factors in decision-making.

6.
Angew Chem Int Ed Engl ; 62(25): e202302505, 2023 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-36992624

RESUMEN

Although solid-state batteries (SSBs) are high potential in achieving better safety and higher energy density, current solid-state electrolytes (SSEs) cannot fully satisfy the complicated requirements of SSBs. Herein, a covalent organic framework (COF) with multi-cationic molecular chains (COF-MCMC) was developed as an efficient SSE. The MCMCs chemically anchored on COF channels were generated by nano-confined copolymerization of cationic ionic liquid monomers, which can function as Li+ selective gates. The coulombic interaction between MCMCs and anions leads to easier dissociation of Li+ from coordinated states, and thus Li+ transport is accelerated. While the movement of anions is restrained due to the charge interaction, resulting in a high Li+ conductivity of 4.9×10-4  S cm-1 and Li+ transference number of 0.71 at 30 °C. The SSBs with COF-MCMC demonstrate an excellent specific energy density of 403.4 Wh kg-1 with high cathode loading and limited Li metal source.


Asunto(s)
Estructuras Metalorgánicas , Estructuras Metalorgánicas/química , Conductividad Eléctrica , Cationes , Litio , Suministros de Energía Eléctrica
7.
Sensors (Basel) ; 22(19)2022 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-36236767

RESUMEN

With the wide application of autonomous mobile robots (AMRs), the visual inertial odometer (VIO) system that realizes the positioning function through the integration of a camera and inertial measurement unit (IMU) has developed rapidly, but it is still limited by the high complexity of the algorithm, the long development cycle of the dedicated accelerator, and the low power supply capacity of AMRs. This work designs a reconfigurable accelerated core that supports different VIO algorithms and has high area and energy efficiency, precision, and speed processing characteristics. Experimental results show that the loss of accuracy of the proposed accelerator is negligible on the most authoritative dataset. The on-chip memory usage of 70 KB is at least 10× smaller than the state-of-the-art works. Thus, the FPGA implementation's hardware-resource consumption, power dissipation, and synthesis in the 28 nm CMOS outperform the previous works with the same platform.

8.
ACS Nano ; 15(11): 18363-18373, 2021 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-34694767

RESUMEN

Lithium-sulfur batteries (LSBs) are still severely blocked by the shuttle of polysulfides (LiPSs), resulting in low sulfur utilization and decreased lifetime. The optimal design of hosts with tailored porous structures and catalytic sites is expected to address this issue. Herein, a Bi/Bi2O3 heterostructure within the metal-organic framework (MOF)-derived sulfur host with a hierarchical structure was elaborated for both serving as sulfur hosts and promoting the redox reaction kinetics of LiPSs. The shuttle effects of LiPSs can be mitigated by the dual functional Bi/Bi2O3 heterostructure enriched in the outer layer of CAU-17-derived carbonic rods, i.e., the effective redox conversion of LiPSs can be realized at the Bi/Bi2O3 heterointerface by the adsorption of LiPSs over Bi2O3 and subsequently catalytic conversion over Bi. Benefiting from these merits, the fabricated LSBs realized a significantly optimized performance, including a high discharge capacity of 740.8 mAh g-1 after 1000 cycles with an ultralow decay rate of 0.022% per cycle at 1 C, a high areal capacity of 6.6 mAh cm-2 after 100 cycles with a sulfur loading of 8.1 mg cm-2, and good performance in pouch cells as well.

9.
Inorg Chem ; 60(15): 11032-11037, 2021 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-34250806

RESUMEN

A highly electronegative carboxyl-decorated anionic metal-organic framework (MOF), (Me2NH2)2[In2(THBA)2](CH3CN)9(H2O)21 (InOF; H4THBA = [1,1':4',1″-terphenyl]-2',3,3″,5,5',5″-hexacarboxylic acid), with high-density electronegative functional sites was designed and constructed. One unit cell of InOF possesses 12 negative sites that originate from the negatively charged secondary building unit [In(COO)4]- and exposed carboxyl groups on the ligand. The abundant electronegative sites can facilitate the hopping of ions in channels and thus result in highly efficient ion conductivities for various metal ions. Our results show that Li+-loaded materials have a remarkably high ion conductivity of 1.49 × 10-3 S/cm, an ion transference number of 0.78, and a relatively low activation energy of 0.19 eV. The Na+, K+, and Zn2+ ion conductivities of InOF are 7.97 × 10-4, 7.69 × 10-4, and 1.22 × 10-3 S/cm at 25 °C, respectively.

10.
Dalton Trans ; 50(8): 2928-2935, 2021 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-33650596

RESUMEN

Metal-organic frameworks (MOFs) have recently emerged as promising solid electrolytes (SEs) for solid-state batteries (SSBs). Developing MOFs with high-density functional groups may improve the spatial density of hopping sites and facilitate ion transport. Herein we synthesized a new series of ion conductive MOFs, Zr-MA-M (M = Li+, Na+, K+, Zn2+), with high density -SH groups functionalized in small pores and metal ions adsorbed on the thiol groups. Taking advantage of the interaction between S and metal ions, such ion conductors show high ionic conductivity, low interfacial resistance, high lithium ion (Li+) transference number (0.63) and wide electrochemical window up (4.6 V). Moreover, the SSBs assembled with Zr-MA-Li+ based SE exhibit excellent rate performance (106 mA h g-1 at 2C) and remarkable cyclic stability (low decay rate of 0.21‰ per cycle for 700 cycles at 2C). Thus, this study provides a new route for developing high-performance MOF-based SEs via the application of host-guest interaction.

11.
J Food Sci Technol ; 55(9): 3485-3497, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30150807

RESUMEN

Curcumin, a natural polyphenolic compound, offers a wide range of pharmacological benefits such as antioxidant, anti-inflammatory and anti-cancer. The oil-in-water nanoemulsions containing curcumin were obtained by high pressure homogenization and effects of various emulsifiers (Tween-80, lecithin, whey protein isolate and acacia) and different surfactant-to-oil ratios (SOR) on physicochemical characteristics, physical stability and storage stability of curcumin loaded nanoemulsions were evaluated in this study. The result showed that smaller particle size, better physical and storage stabilities and higher curcumin content were found in curcumin loaded nanoemulsions stabilized with Tween-80 and lecithin. Compared with nanoemulsions prepared with lecithin, nanoemulsions fabricated with Tween-80 exhibited better uniformity and distribution as demonstrated by microscopic observations. It was found that SOR was positively correlated with particle size but negatively correlated with curcumin content in the emulsion droplets. Neither the emulsifier nor SOR values were found to have significant effects on zeta-potentials of the droplets. This result implied that curcumin loaded nanoemulsions prepared with Tween-80 and higher SOR values helped curcumin to achieve better physical stability and storage stability.

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