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1.
Small ; 20(44): e2403660, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39004850

RESUMO

All-solid-state lithium metal batteries (ASSLMBs) have emerged as the most promising next-generation energy storage devices. However, the unsatisfactory ionic conductivity of solid electrolytes at room temperature has impeded the advancement of solid-state batteries. In this work, a multifunctional composite solid electrolyte (CSE) is developed by incorporating boron nitride nanotubes (BNNTs) into polyvinylidene fluoride-hexafluoropropylene (PVDF-HFP). BNNTs, with a high aspect ratio, trigger the dissociation of Li salts, thus generating a greater population of mobile Li+, and establishing long-distance Li+ transport pathways. PVDF-HFP/BNNT exhibits a high ionic conductivity of 8.0 × 10-4 S cm-1 at room temperature and a Li+ transference number of 0.60. Moreover, a Li//Li symmetric cell based on PVDF-HFP/BNNT demonstrates robust cyclic performance for 3400 h at a current density of 0.2 mA cm-2. The ASSLMB formed from the assembly of PVDF-HFP/BNNT with LiFePO4 and Li exhibits a capacity retention of 93.2% after 850 cycles at 0.5C and 25 °C. The high-voltage all-solid-state LiCoO2/Li cell based on PVDF-HFP/BNNT also exhibits excellent cyclic performance, maintaining a capacity retention of 96.4% after 400 cycles at 1C and 25 °C. Furthermore, the introduction of BNNTs is shown to enhance the thermal conductivity and flame retardancy of the CSE.

2.
J Phys Chem Lett ; 15(7): 1921-1929, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38345930

RESUMO

Chemical vapor deposition (CVD) stands out as the most promising method for cost-effective production of high-quality boron nitride nanotubes (BNNTs). Catalysts play a crucial role in BNNT synthesis. This work delves into the impact of oxygen (O) on Ti-based catalysts during the CVD growth of BNNTs. In contrast to the B/TiB2 nanoparticles (NPs) and B/TiN NPs systems, the oxygen-containing precursor B/TiO2 NPs remarkably catalyzes the growth of high-quality and high-purity BNNTs across a wider range of synthesis parameters. Subsequent analyses reveal that TiBO3 acts as an active catalyst, facilitating BNNT growth in Ti-based catalyst systems. Moreover, the nanocomposite film synthesized from BNNTs and PVDF-HFP exhibits excellent mechanical properties and heat dissipation capabilities. Utilizing the nanocomposite film as a thermal interface material effectively enhances the heat dissipation for a 5 W light-emitting diode (LED) chip. Consequently, our research confirms the effectiveness of the Ti-B-O system in catalyzing BNNT growth.

3.
ACS Appl Mater Interfaces ; 15(47): 54886-54897, 2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-37963338

RESUMO

Emerging biocomposites with excellent heat dissipation capabilities and inherent sustainability are urgently needed to address the cooling issues of modern electronics and growing environmental concerns. However, the moisture stability, mechanical performance, thermal conductivity, and even flame retardancy of biomass-based materials are generally insufficient for practical thermal management applications. Herein, we present a high-performance graphene biocomposite consisting of carboxylated cellulose nanofibers and graphene nanosheets through an evaporation-induced self-assembly and subsequent Fe3+ cross-linking strategy. The Fe3+ coordination plays a critical role in stabilizing the material structure, thereby improving the mechanical strength and water stability of the biocomposite films, and its effect is revealed by density functional theory calculations. The hierarchical structure of the biocomposite films also leads to a high in-plane thermal conductivity of 42.5 W m-1 K-1, enabling a superior heat transfer performance. Furthermore, the resultant biocomposite films exhibit outstanding Joule heating performance with a fast thermal response and long-term stability, improved thermal stability, and flame retardancy. Therefore, such a general strategy and the desired overall properties of the biocomposite films offer wide application prospects for functional and safe thermal management.

4.
Molecules ; 28(18)2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37764479

RESUMO

Chuanxiong rhizoma (CX) has been utilized for centuries as a traditional herb to treat blood stasis syndromes. However, the pharmacological mechanisms are still not completely revealed. This research was aimed at exploring the molecular mechanisms of CX treatment for thrombosis. Network pharmacology was used to predict the potential anti-thrombosis mechanism after correlating the targets of active components with targets of thrombosis. Furthermore, we verified the mechanism of using CX to treat thrombosis via molecular docking and in vitro experiments. Network pharmacology results showed that a total of 18 active ingredients and 65 targets of CX treatment for thrombosis were collected, including 8 core compounds and 6 core targets. We revealed for the first time that tissue factor (TF) had a close relationship with most core targets of CX in the treatment of thrombosis. TF is a primary coagulation factor in physiological hemostasis and pathological thrombosis. Furthermore, core components of CX have strong affinity for core targets and TF according to molecular docking analysis. The in vitro experiments indicated that Ligustilide (LIG), the representative component of CX, could inhibit TF procoagulant activity, TF mRNA and protein over-expression in a dose-dependent manner in EA.hy926 cells through the PI3K/Akt/NF-κB signaling pathway. This work demonstrated that hemostasis or blood coagulation was one of the important biological processes in the treatment of thrombosis with CX, and TF also might be a central target of CX when used for treating thrombosis. The inhibition of TF might be a novel mechanism of CX in the treatment of thrombosis.


Assuntos
Farmacologia em Rede , Trombose , Humanos , Simulação de Acoplamento Molecular , Fosfatidilinositol 3-Quinases , Trombose/tratamento farmacológico , Coagulação Sanguínea
5.
Kaohsiung J Med Sci ; 39(6): 605-615, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36960852

RESUMO

Chemotherapy is one of the common treatment methods for breast cancer, but chemoresistance is a severe challenge. Caffeic acid phenethyl ester (CAPE) is an active ingredient of propolis extract and has been shown to have a variety of beneficial effects, and its potential as a treatment for breast cancer is worth exploring. The effects of CAPE on doxorubicin (DOX) resistance were determined by cell counting kit-8 (CCK-8) assay, colony-formation assay, and flow cytometry. Oil Red O staining and the detection of free fatty acids, triglycerides, phospholipids, and cholesterol were performed to assess the status of lipid metabolism. Quantitative polymerase chain reaction (qPCR) and western blotting were applied to investigate the molecules involved in lipid metabolism and the protein kinase B (Akt)/mammalian target of rapamycin (mTOR)/sterol regulatory element binding protein 1 (SREBP1) pathway. CAPE treatment reversed DOX resistance in breast cancer cells and suppressed their lipid metabolism. In addition, CAPE combined with DOX remarkably suppressed SREBP1 expression in part by inhibiting Akt/mTOR pathway activation. Furthermore, by inhibiting lipid metabolism, partly via the Akt/mTOR/SREBP1 pathway, CAPE ultimately reversed DOX resistance in breast cancer. Our results suggest that CAPE treatment reversed DOX resistance in breast cancer cells, at least in part by inhibiting Akt/mTOR/SREBP1 pathway-mediated lipid metabolism, indicating that CAPE may be an effective substance to assist in the treatment of breast cancer.


Assuntos
Neoplasias da Mama , Proteínas Proto-Oncogênicas c-akt , Humanos , Feminino , Proteínas Proto-Oncogênicas c-akt/genética , Transdução de Sinais , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/farmacologia , Metabolismo dos Lipídeos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Serina-Treonina Quinases TOR/genética , Doxorrubicina/farmacologia , Linhagem Celular Tumoral
6.
Small ; 19(14): e2206933, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36631285

RESUMO

The large-scale synthesis of high-quality boron nitride nanotubes (BNNTs) has attracted considerable interests due to their applications in nanocomposites, thermal management, and so on. Despite decades of development, efficient preparation of high-quality BNNTs, which relies on the effective design of precursors and catalysts and deep insights into the catalytic mechanisms, is still urgently needed. Here, a self-catalytic process is designed to grow high-quality BNNTs using ternary W-B-Li compounds. W-B-Li compounds provide boron source and catalyst for BNNTs growth. High-quality BNNTs are successfully obtained via this approach. Density functional theory-based molecular dynamics (DFT-MD) simulations demonstrate that the Li intercalation into the lattice of W2 B5 promotes the formation of W-B-Li liquid and facilitates the compound evaporation for efficient BNNTs growth. This work demonstrates a high-efficient self-catalytic growth of high-quality BNNTs via ternary W-B-Li compounds, providing a new understanding of high-quality BNNTs growth.

7.
Front Chem ; 10: 1035949, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36385999

RESUMO

Camellia fascicularis is a unique plant rich in bioactive components. However, the isolation of the active substances in C. fascicularis leaves via sequential extraction with solvents of different polarity and the determination of their antioxidant and antitumor activities have not been reported. In this study, the total methanol extract of C. fascicularis leaves was sequentially extracted with different polar solvents, and the corresponding petroleum ether extract (PEE), ethyl acetate extract (EAE), and water extract (WE) were analyzed for their contents in active substances such as flavonoids, polyphenols, polysaccharides, and saponins. The antioxidant ability of the polar extracts was investigated by determining their reducing power and the radical scavenging rate on 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and hydroxyl radicals, and CCK-8 and Annexin-FITC/propidium iodide staining assays were conducted to investigate their inhibitory effects on HCCLM6 and HGC27 tumor cells. The results showed that PEE had a high saponin content of 197.35 ± 16.21 mg OAE/g, while EAE and WE exhibited a relatively higher polysaccharide content of 254.37 ± 1.99 and 373.27 ± 8.67 mg GE/g, respectively. The EAE demonstrated the greatest reducing power and the strongest clearing abilities on ABTS and DPPH radicals with respective EC50 values of 343.45 ± 20.12 and 14.07 ± 0.06 µg/ml. Moreover, the antitumor ability of the different polar extracts was dose-dependent, with WE showing the most potent inhibitory ability against HCCLM6 and HGC27 cells.

8.
Chem Commun (Camb) ; 58(87): 12216-12219, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36250481

RESUMO

We propose an efficient strategy based on the electrospinning technique combined with multi-dimensional fillers to fabricate composites with well-established thermal pathways. A bridge-type structure is constructed in the composite fibers by integrating 1D boron nitride nanofibers and 2D boron nitride nanosheets, which can accelerate the formation of a valid thermal network, thereby the BNNS/BNNF/polyacrylonitrile (bsf) composites perform better than the BNNS/polyacrylonitrile (bs) composites. This strategy can be extended to the preparation of other electrospun 1D/2D nanofiller/polymer composite fiber films.

9.
Chem Commun (Camb) ; 58(33): 5096-5099, 2022 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-35380564

RESUMO

We report a strategy that tunes the CO2 and proton concentrations near the electrode-electrolyte interface using surfactant modification with various amounts (0.05, 0.8, 1.6, and 3.2 mg) of hexadecyl trimethyl ammonium bromide (CTAB). The positively charged group of CTAB favors CO2 surface diffusion and inhibits excessive proton accumulation on Zn nanosheets on carbon paper. A CO faradaic efficiency of 95.6% and a total ampere density of -13.1 mA cm-2 were obtained over the optimal CTAB-modified Zn electrode at -1.1 V with stability over 12 hours.

10.
Z Naturforsch C J Biosci ; 76(1-2): 11-19, 2021 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-32614784

RESUMO

Tissue factor (TF) which plays a key role in hemostasis and thrombosis appears to be an attractive target and medicinal plants having alkaloids inhibition TF activity benefit to cardiovascular disease (CVD). The aim of study is to explore further knowledge about alkaloids and TF. TF procoagulant activities were determined by the simplified chromogenic assay and their mRNA expression were then examined by reverse transcription and polymerase chain reaction. Besides, the potential of TF/FVIIa binding with four representative alkaloids were analyzed by molecular docking. The results indicated that these isoquinoline alkaloids with various structures had a different effect on suppression of TF activity. Molecular docking showed four alkaloids including l-corydalmine, berberine, jatrorrhizine, and tetrahydropalmatine were stably posed in the active binding pocket of TF/FVIIa. The SARs analysis showed the structural difference including planar, quaternary nitrogen, and the peripheral functional groups at C-8, C-9, C-10, have strong effect on inhibition of TF activity, which provided effective methods to modify isoquinoline alkaloids for inhibiting TF activity. This study provides a further evidence for the cardiovascular protection of isoquinoline alkaloids, and has physiological significance in the clinical challenge to use isoquinoline alkaloids or their potential analogs in the treatment of CVD.


Assuntos
Alcaloides/química , Isoquinolinas/química , Simulação de Acoplamento Molecular , Tromboplastina/metabolismo , Alcaloides/farmacologia , Sítios de Ligação , Células Cultivadas , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Isoquinolinas/farmacologia , Ligação Proteica , Relação Estrutura-Atividade , Tromboplastina/química
11.
Ying Yong Sheng Tai Xue Bao ; 22(11): 2861-7, 2011 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-22303662

RESUMO

Rice productivity is the key factor affecting rice production and its sustainable development. Based on the gradation of cultivated land quality at county-level, this paper evaluated the rice productivity in Fuyang County of Zhejiang Province, and, through selected sampling field investigation and according to the land productivity index of paddy field quality, a model for assessing rice achievable productivity was established, aimed to analyze the regional rice productivity and its achievable productivity. In the study area, there was a positive correlation between the land productivity index and rice yield. For single cropping rice, its achievable productivity was 1.70 x 10(5) t, being 1.6 times of its realistic productivity (1.04 x 10(5) t). In 2009, the realistic rice productivity per unit area was 7676 kg x hm(-2), and the achievable productivity was 8831 kg x hm(-2), with a production potentiality of +15%, a big potential of rice production capacity in the county. Through the analyses of rice productivity, relative superiority of rice production scale, and its growth potential index in the villages and towns, the rice production of Fuyang County was divided into three regions, i. e., key enhancement region, optimization construction region, and development protection region.


Assuntos
Agricultura/métodos , Biomassa , Abastecimento de Alimentos/estatística & dados numéricos , Oryza/crescimento & desenvolvimento , China , Previsões , Modelos Teóricos , Solo/análise
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