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1.
Int J Biol Macromol ; 263(Pt 2): 130211, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38423902

RESUMEN

Nanocatalysts are vital in several domains, such as chemical processes, energy generation, energy preservation, and environmental pollution mitigation. An experimental study was conducted at room temperature to evaluate the catalytic activity of the new gelatin-chitosan hydrogel/CuO/Fe3O4 nanocomposite in the asymmetric Hantzsch reaction. All components of the nanocomposite exhibit a synergistic effect as a Lewis acid, promote the reaction. Dimedone, ammonium acetate, ethyl acetoacetate, and other substituted aldehydes were used to synthesize diverse polyhydroquinoline derivatives. The nanocomposite exhibited exceptional efficacy (over 90 %) and durability (retaining 80 % of its original capacity after 5 cycles) as a catalyst in the one-pot asymmetric synthesis of polyhydroquinoline derivatives. Also, turnover numbers (TON) and turnover frequency (TOF) have been checked for catalyst (TON and TOF = 50,261 and 100,524 h-1) and products. The experiment demonstrated several benefits, such as exceptional product efficacy, rapid reaction time, functioning at ambient temperature without specific requirements, and effortless separation by the use of an external magnet after the reaction is finished. The results suggest the development of a magnetic nanocatalyst with exceptional performance. The composition of the Ge-CS hydrogel/CuO/Fe3O4 nanocomposite was thoroughly analyzed using several methods including FT-IR, XRD, FE-SEM, EDX, VSM, BET, and TGA. These analyses yielded useful information into the composition and characteristics of the nanocomposite, hence further enhancing the knowledge of its possible uses.


Asunto(s)
Quitosano , Nanocompuestos , Nanopartículas , Quitosano/química , Cobre/química , Gelatina , Espectroscopía Infrarroja por Transformada de Fourier , Hidrogeles , Fenómenos Magnéticos , Óxidos , Nanocompuestos/química
3.
Sci Rep ; 14(1): 970, 2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-38200095

RESUMEN

The treatment of methylene blue (MB) dye wastewater through the adsorption process has been a subject of extensive research. However, a comprehensive understanding of the thermodynamic aspects of dye solution adsorption is lacking. Previous studies have primarily focused on enhancing the adsorption capacity of methylene blue dye. This study aimed to develop an environmentally friendly and cost-effective method for treating methylene blue dye wastewater and to gain insights into the thermodynamics and kinetics of the adsorption process for optimization. An adsorbent with selective methylene blue dye adsorption capabilities was synthesized using rice straw as the precursor. Experimental studies were conducted to investigate the adsorption isotherms and models under various process conditions, aiming to bridge gaps in previous research and enhance the understanding of adsorption mechanisms. Several adsorption isotherm models, including Langmuir, Temkin, Freundlich, and Langmuir-Freundlich, were applied to theoretically describe the adsorption mechanism. Equilibrium thermodynamic results demonstrated that the calculated equilibrium adsorption capacity (qe) aligned well with the experimentally obtained data. These findings of the study provide valuable insights into the thermodynamics and kinetics of methylene blue dye adsorption, with potential applications beyond this specific dye type. The utilization of rice straw as an adsorbent material presents a novel and cost-effective approach for MB dye removal from wastewater.

4.
J Mol Model ; 29(12): 381, 2023 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-37985487

RESUMEN

CONTEXT: The catalytic ability of Sc-doped C46 and Sc-doped Al23P23 as catalysts of CO2-RR to create the CH4 and CH3OH is investigated. The mechanisms of CO2-RR are examined by theoretical methods and ΔGreaction of reaction steps of CO2-RR mechanisms are calculated. The overpotential of CH4 and CH3OH production on Sc-doped C46 and Sc-doped Al23P23 is calculated. The Sc atoms of Sc-doped C46 and Sc-doped Al23P23 can adsorb the CO2 molecule as the first step of CO2-RR. The CH4 is produced from hydrogenation of *CH3O and the *CO → *CHO reaction step is the rate limiting step for CH4 production. The CH3OH can be formed on Sc-doped C46 and Sc-doped Al23P23 by *CO → *CHO → *CH2O → *CH3O → CH3OH mechanism and HCOOH → *CHO → *CH2O → *CH3O → CH3OH mechanism. The Sc-C46 and Sc-Al23P23 can catalyze the CO2-RR to produce the CH4 and CH3OH by acceptable mechanisms. METHODS: Here, the structures are optimized by PW91PW91/6-311+G (2d, 2p) and M06-2X/cc-pVQZ methods in GAMESS software. The frequencies of nanocages and their complexes with species of CO2-RR are investigated by mentioned methods. The transition state of each reaction step of CO2-RR is searched by Berny method to find the CO2-RR intermediates. The ∆Eadsorption of intermediates of CO2-RR on surfaces of nanocages is calculated and the ∆Greaction of reaction steps of CO2-RR is calculated.

5.
Pathol Res Pract ; 248: 154631, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37393667

RESUMEN

MicroRNA-126 (miR-126) has become a key player in the biology of cancer, playing a variety of functions in carcinogenesis and cancer development. The diagnostic and prognostic potential of miR-126 in diverse cancer types is summarized in this thorough analysis, with an emphasis on its role in tumor angiogenesis, invasion, metastasis, cell proliferation, apoptosis, and treatment resistance. MiR-126 dysregulation is linked to a higher risk of developing cancer and a worse prognosis. Notably, miR-126 affects tumor vascularization and development by targeting vascular endothelial growth factor-A (VEGF-A). Through its impact on genes involved in cell adhesion and migration, it also plays a vital part in cancer cell invasion and metastasis. Additionally, miR-126 controls drug resistance, apoptosis, and cell proliferation, which affects cancer cell survival and treatment response. It may be possible to develop innovative therapeutic approaches to stop tumor angiogenesis, invasion, and metastasis, as well as combat drug resistance by focusing on miR-126 or its downstream effectors. The versatility of miR-126's functions highlights the role that it plays in cancer biology. To understand the processes behind miR-126 dysregulation, pinpoint precise targets, and create efficient therapies, more investigation is required. Utilizing miR-126's therapeutic potential might have a significant influence on cancer treatment plans and patient outcomes.


Asunto(s)
MicroARNs , Humanos , MicroARNs/genética , MicroARNs/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo , Línea Celular Tumoral , Movimiento Celular/genética , Neovascularización Patológica/genética , Neovascularización Patológica/metabolismo , Carcinogénesis/genética , Proliferación Celular , Regulación Neoplásica de la Expresión Génica/genética
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