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1.
Front Mol Neurosci ; 17: 1398665, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38836117

RESUMO

Background: Multiple sclerosis (MS) is an immune-mediated disease characterized by inflammatory demyelinating lesions in the central nervous system. Studies have shown that the inflammation is vital to both the onset and progression of MS, where aging plays a key role in it. However, the potential mechanisms on how aging-related inflammation (inflammaging) promotes MS have not been fully understood. Therefore, there is an urgent need to integrate the underlying mechanisms between inflammaging and MS, where meaningful prediction models are needed. Methods: First, both aging and disease models were developed using machine learning methods, respectively. Then, an integrated inflammaging model was used to identify relative risk factors, by identifying essential "aging-inflammation-disease" triples. Finally, a series of bioinformatics analyses (including network analysis, enrichment analysis, sensitivity analysis, and pan-cancer analysis) were further used to explore the potential mechanisms between inflammaging and MS. Results: A series of risk factors were identified, such as the protein homeostasis, cellular homeostasis, neurodevelopment and energy metabolism. The inflammaging indices were further validated in different cancer types. Therefore, various risk factors were integrated, and even both the theories of inflammaging and immunosenescence were further confirmed. Conclusion: In conclusion, our study systematically investigated the potential relationships between inflammaging and MS through a series of computational approaches, and could present a novel thought for other aging-related diseases.

2.
Chemistry ; 30(23): e202304266, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38369590

RESUMO

The exploration of stable, efficient, and low-cost catalysts toward ammonia borane hydrolysis is of vital significance for the practical implementation of this hydrogen production technology. Integrating interface engineering and nano-architecture engineering is a favorable strategy to elevate catalytic performance, as it can modify the electronic structure and provide sufficient active sites simultaneously. In this work, urchin-like NiCoP/CoP heterostructures are prepared via a three-step hydrothermal-oxidation-phosphorization synthesis route. It is demonstrated that the original Ni/Co molar ratio and the amount of phosphorus are crucial for adjusting the morphology, enhancing the exposed surface area, facilitating charge transfer, and modulating the adsorption and activation of H2O molecules. Consequently, the optimal Ni1Co2P heterostructure displays remarkable catalytic properties in the hydrolysis of ammonia borane with a turnover frequency (TOF) value of 30.3 molH2 ⋅ min-1 ⋅ molmetal -1, a low apparent activation energy of 25.89 kJ ⋅ mol-1, and good stability. Furthermore, by combining infrared spectroscopy and isotope kinetics experiments, a possible mechanism for the hydrolysis of ammonia borane was proposed.

3.
Nat Commun ; 14(1): 5668, 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37704640

RESUMO

For decarbonization of ammonia production in industry, alternative methods by exploiting renewable energy sources have recently been explored. Nonetheless, they still lack yield and efficiency to be industrially relevant. Here, we demonstrate an advanced approach of nitrogen fixation to synthesize ammonia at ambient conditions via laser-induced multiphoton dissociation of lithium oxide. Lithium oxide is dissociated under non-equilibrium multiphoton absorption and high temperatures under focused infrared light, and the generated zero-valent metal spontaneously fixes nitrogen and forms a lithium nitride, which upon subsequent hydrolysis generates ammonia. The highest ammonia yield rate of 30.9 micromoles per second per square centimeter is achieved at 25 °C and 1.0 bar nitrogen. This is two orders of magnitude higher than state-of-the-art ammonia synthesis at ambient conditions. The focused infrared light here is produced by a commercial simple CO2 laser, serving as a demonstration of potentially solar pumped lasers for nitrogen fixation and other high excitation chemistry. We anticipate such laser-involved technology will bring unprecedented opportunities to realize not only local ammonia production but also other new chemistries .

4.
J Colloid Interface Sci ; 650(Pt B): 1648-1658, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37494861

RESUMO

The design and fabrication of cheap and high-efficiency catalysts for ammonia borane (AB) hydrolysis for hydrogen production is crucial for its commercial applications. Improvement of the catalytic performance of the catalysts with the assistance of sunlight, a costless resource, is extremely attractive. Herein, we have constructed Z-scheme heterostructured VO-NiO-CuO catalysts with strong interfacial electronic interactions and abundant oxygen vacancies to enhance hydrogen production from NH3BH3 solution under visible light illumination. The as-prepared VO-NiO-CuO catalysts exhibit excellent catalytic activity with a high turnover frequency (TOF) of 35.3 molH2 molcat.-1 min-1 toward AB hydrolysis under visible light. It is demonstrated that excellent catalytic performance is highly related to the effective separation and migration of charge on the catalyst surface. As a result, dual active sites were created, making it easier for various reactants to be adsorbed and activated on the catalyst surface. Furthermore, the density functional theory (DFT) calculations indicate that the adsorption and activation of H2O occurred mainly at the Ni site of VO-NiO-CuO. When the VO-NiO-CuO is irradiated with visible light, the photogenerated electrons assembled on the conduction band were transferred to the O atom through the Ni-O bond, which made the bond length of H2O molecules longer and OH bonds more prone to breaking, thus facilitating AB hydrolysis under illumination. The findings in this work pave the way to design novel and efficient heterostructured catalysts for fast hydrogen release from NH3BH3 under visible light irradiation.

5.
Adv Mater ; 35(38): e2211054, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36841955

RESUMO

Fabricating electronic devices from natural, renewable resources is a common goal in engineering and materials science. In this regard, carbon is of special significance due to its biocompatibility combined with electrical conductivity and electrochemical stability. In microelectronics, however, carbon's device application is often inhibited by tedious and expensive preparation processes and a lack of control over processing and material parameters. Laser-assisted carbonization is emerging as a tool for the precise and selective synthesis of functional carbon-based materials for flexible device applications. In contrast to conventional carbonization via in-furnace pyrolysis, laser-carbonization is induced photo-thermally and occurs on the time-scale of milliseconds. By careful selection of the precursors and process parameters, the properties of this so-called laser-patterned carbon (LP-C) such as porosity, surface polarity, functional groups, degree of graphitization, charge-carrier structure, etc. can be tuned. In this critical review, a common perspective is generated on laser-carbonization in the context of general carbonization strategies, fundamentals of laser-induced materials processing, and flexible electronic applications, like electrodes for sensors, electrocatalysts, energy storage, or antennas. An attempt is made to have equal emphasis on material processing and application aspects such that this emerging technology can be optimally positioned in the broader context of carbon-based microfabrication.

6.
ACS Appl Mater Interfaces ; 14(24): 27979-27993, 2022 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-35674395

RESUMO

Rational construction of inexpensive, highly efficient, and stable catalysts for ammonia borane (AB) methanolysis is in high demand but still remains a great challenge. In this work, we have successfully fabricated uniform Mox-Ni0.8Cu0.2O nanowires using a simple hydrothermal method followed by a post-calcination treatment and flexibly modulated the acidity of their surface by changing the amount of Mo introduced into Ni0.8Cu0.2O. The Mo0.1-Ni0.8Cu0.2O catalyst displayed strong catalytic activity toward AB methanolysis with an ultrahigh turnover frequency of 46.9 molH2 molcat.-1 min-1, which is even higher than some noble metal catalysts. In this work, an equation regarding the relationship between the quantity of moderated acid sites of catalysts and its corresponding activity toward AB methanolysis was first determined. A plausible mechanism for AB methanolysis catalyzed by Mox-Ni0.8Cu0.2O was proposed, and the benefits of the introduction of MoO3 to Ni0.8Cu0.2O for enhancing the catalytic performance were also discussed. These findings can form a basis for the rational construction of inexpensive catalysts with robust performance toward AB methanolysis for hydrogen production.

7.
Int J Clin Exp Pathol ; 14(5): 582-595, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34093944

RESUMO

BACKGROUND: Glioblastoma (GBM) is an aggressive brain tumor and the mechanisms of progression are very complex. Accelerated aging is a driving factor of GBM. However, there has not been thorough research about the mechanisms of GBM progression based on aging acceleration. METHODS: The aging predictor was modeled based on normal brain samples. Then an aging acceleration background network was constructed to explore GBM mechanisms. RESULTS: The accelerated aging-related mechanisms provided an innovative way to study GBM, wherein integrative analysis of somatic mutations and differential expression revealed key pathologic characteristics. Moreover, the influence of the immune system, the nervous system and other critical factors on GBM were identified. The survival analysis also disclosed crucial GBM markers. CONCLUSION: An integrative analysis of multi-omics data based on aging acceleration identified new driving factors for GBM.

8.
Chem Sci ; 11(31): 8256-8266, 2020 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-34094179

RESUMO

Luminescent compounds obtained from the thermal reaction of citric acid and urea have been studied and utilized in different applications in the past few years. The identified reaction products range from carbon nitrides over graphitic carbon to distinct molecular fluorophores. On the other hand, the solid, non-fluorescent reaction product produced at higher temperatures has been found to be a valuable precursor for the CO2-laser-assisted carbonization reaction in carbon laser-patterning. This work addresses the question of structural identification of both, the fluorescent and non-fluorescent reaction products obtained in the thermal reaction of citric acid and urea. The reaction products produced during autoclave-microwave reactions in the melt were thoroughly investigated as a function of the reaction temperature and the reaction products were subsequently separated by a series of solvent extractions and column chromatography. The evolution of a green molecular fluorophore, namely HPPT, was confirmed and a full characterization study on its structure and photophysical properties was conducted. The additional blue fluorescence is attributed to oligomeric ureas, which was confirmed by complementary optical and structural characterization. These two components form strong hydrogen-bond networks which eventually react to form solid, semi-crystalline particles with a size of ∼7 nm and an elemental composition of 46% C, 22% N, and 29% O. The structural features and properties of all three main components were investigated in a comprehensive characterization study.

9.
Nanomaterials (Basel) ; 9(9)2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31540373

RESUMO

The catalytic hydrolysis of ammonia borane (AB) is a promising route to produce hydrogen for mobile hydrogen‒oxygen fuel cells. In this study, we have successfully synthesized a variety of Ni0.5Cu0.5Co2O4 nanocomposites with different morphology, including nanoplatelets, nanoparticles, and urchin-like microspheres. The catalytic performance of those Ni0.5Cu0.5Co2O4 composites in AB hydrolysis is investigated. The Ni0.5Cu0.5Co2O4 nanoplatelets show the best catalytic performance despite having the smallest specific surface area, with a turnover frequency (TOF) of 80.2 molhydrogen·min-1·mol-1cat. The results reveal that, in contrast to the Ni0.5Cu0.5Co2O4 nanoparticles and microspheres, the Ni0.5Cu0.5Co2O4 nanoplatelets are more readily reduced, leading to the fast formation of active species for AB hydrolysis. These findings provide some insight into the design of high-performance oxide-based catalysts for AB hydrolysis. Considering their low cost and high catalytic activity, Ni0.5Cu0.5Co2O4 nanoplatelets are a strong candidate catalyst for the production of hydrogen through AB hydrolysis in practical applications.

10.
Chem Commun (Camb) ; 54(40): 5058-5061, 2018 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-29726871

RESUMO

A simple charge modulation approach has been developed to stabilize naked Au clusters on a nanoporous conjugated organic network. Through engineering pore walls with regulated charges, the controllable growth of Au nanoclusters has been realized. The resulting supported catalyst exhibits excellent performance in the aerobic oxidation of alcohols.

11.
Se Pu ; 30(1): 107-10, 2012 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-22667103

RESUMO

A method for the simultaneous determination of glyoxalate and oxalate by capillary zone electrophoresis (CZE) was developed. The influences of type, concentration and pH of the running buffer, and the applied voltage on separation were investigated. Glyoxalate and oxalate were separated within 11 min under the conditions of 20 mmol/L borax-5.5 mmol/L potassium hydrogen phthalate (pH 9.0), applied voltage of 20 kV, and detected wavelength of 212 nm. The calibration curves of glyoxalate and oxalate showed good linearity in the ranges of 0.8 -20 g/L and 1.2-20 g/L, respectively. The correlation coefficients were 0.999 3 and 0.997 5, respectively. The limits of detection for glyoxalate and oxalate were 0.2 and 0.4 g/L (S/N = 3), respectively. The average recoveries at three spiked levels were 98.3%-102.5% with acceptable relative standard deviations of 0.35%-0.61%. This method is simple, low cost and high performance. The method was successfully used for the determination of glyoxalate and oxalate in real samples, and the assay results were satisfactory.


Assuntos
Eletroforese Capilar/métodos , Glioxilatos/análise , Oxalatos/análise , Sensibilidade e Especificidade
12.
Se Pu ; 28(11): 1111-4, 2010 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-21381433

RESUMO

A method for the simultaneous separation and determination of vanillin and o-vanillin by capillary zone electrophoresis (CZE) was developed. The influences of type, concentration and pH of running buffer, and applied voltage on separation were investigated. Under the conditions of 50 mmol/L borax-150 mmol/L disodium hydrogen phosphate (pH 7.5) and applied voltage of 15 kV, the vanillin and o-vanillin were separated in 6 min. The method was proved to be robust through verification of accuracy, precision and linearity. The calibration curves of vanillin and o-vanillin showed good linearity in the range of 10-240 mg/L, and the correlation coefficients were 0.999 9 and 0.999 7, respectively. The limits of detection for vanillin and o-vanillin were 1.0 mg/L (S/N = 3). The average recoveries at three spiked levels were 99.4%-101.2% with acceptable relative standard deviations of 0.19%-0.73%. The method has been successfully used for the determination of vanillin and o-vanillin in real samples, and the assay results are satisfactory.

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