Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 6 de 6
Filtrar
Más filtros

Banco de datos
Tipo del documento
País de afiliación
Intervalo de año de publicación
1.
Dalton Trans ; 53(12): 5732, 2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38450670

RESUMEN

Correction for 'Porous oligomeric materials synthesised using a new, highly active precatalyst based on ruthenium(III) and 2-phenylpyridine' by Kacper Poblocki et al., Dalton Trans., 2024, 53, 4194-4203, https://doi.org/10.1039/D3DT04091G.

2.
Dalton Trans ; 53(9): 4194-4203, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38323842

RESUMEN

There are few literature reports on using precatalysts based on ruthenium(II/III) ions in the polymerization of olefins. Therefore, a new coordination compound was designed based on ruthenium(III) ion and 2-phenylpyridine. The resulting monocrystal was characterized by X-ray diffraction (XRD), solid-state (photo)IR spectroscopy, scanning electron microscopy (SEM), and thermogravimetric analysis (TGA). The new ruthenium(III) complex compound was used as a precatalyst in the oligomerization reactions of ethylene, 2-propen-1-ol, 2-chloro-2-propen-1-ol, 3-butene-2-ol and 2,3-dibromo-2-propen-1-ol with methylaluminoxane and ethylaluminium dichloride as activators. The catalytic activity of the newly discovered ruthenium(III) complex compound ranges from 159.5 (for 2-chloro-2-propen-1-ol) to 755.6 (for ethylene) g mmol-1 h-1 bar-1, indicating that it is a chemical compound with high catalytic activity. In addition, the oligomerization reaction products were subjected to physicochemical characterization, using BET (Brunauer-Emmett-Teller isotherm), mass spectrometry (MALDI-TOF-MS), Fourier transform infrared (FT-IR) spectroscopy, NMR, TGA, differential scanning calorimetry (DSC), and the morphology of the porous polymeric materials was investigated by SEM. The distinguishing feature of the obtained precatalyst is its high catalytic activity under mild reaction conditions, a rare phenomenon. Compared with other precatalysts, it is the most active ruthenium(II/III) ion-based catalytic material used in oligo- and polymerization reactions of ethylene.

3.
Crit Rev Oncol Hematol ; 197: 104329, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38527594

RESUMEN

PURPOSE: We found a need for balancing the application of clinical guidelines and tailored approaches to follow-up of cervical cancer (CC) patients in the lymph node micrometastatic (MICs) setting. This review aimed to determine the current knowledge of management of MIC-positive CC cases. METHODOLOGY: We addressed prognostic and risk of recurrence monitoring impacts associated with MIC+ cases. The electronic databases for literature and relevant articles were analysed. RESULTS: Fifteen studies, (4882 patients), were included in our systematic review. While the results show that MICs significantly worsen prognosis in early CC. A tertiary prevention algorithm for low volume lymph node disease may stratify follow-up according to the burden of nodal disease and provide data that helps improve follow-up performance. CONCLUSION: MICs worsen prognosis and should be managed as suggested by the algorithm. However, this algorithm must be externally validated. The clinical impact of isolated tumor cells (ITC) remains unclear.


Asunto(s)
Metástasis Linfática , Micrometástasis de Neoplasia , Neoplasias del Cuello Uterino , Femenino , Humanos , Ganglios Linfáticos/patología , Micrometástasis de Neoplasia/patología , Recurrencia Local de Neoplasia/prevención & control , Recurrencia Local de Neoplasia/patología , Pronóstico , Prevención Terciaria/métodos , Neoplasias del Cuello Uterino/patología , Neoplasias del Cuello Uterino/diagnóstico , Neoplasias del Cuello Uterino/prevención & control
4.
Nanomaterials (Basel) ; 9(5)2019 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-31096544

RESUMEN

Ionic liquids (ILs) could serve as a structuring agent, a solvent, or a source of dopant during solvothermal synthesis of semiconductors particles. To understand the role of IL during formation of TiO2 particles, it is necessary to study the stability of this IL in solvothermal synthesis conditions, as well as studying the surface properties of formed TiO2 particles. In view of this, the effect of the 2,3,5-triphenyltetrazolium chloride IL ([TPTZ][Cl]) thermal decomposition during the solvothermal reaction and IL content in the reaction system on photoactivity of TiO2 microparticles has been systematically investigated. The samples obtained by using [TPTZ][Cl] exhibited remarkable photocatalytic properties in phenol degradation reaction under visible light. HPLC analysis of the solvothermal reaction medium and X-ray photoelectron spectroscopy (XPS) analysis of TiO2 particles revealed that [TPTZ][Cl] was decomposed completely and was incorporated into the TiO2 lattice. Generally, increasing the reaction time (1, 4, 12, and 24 h) promoted the TiO2 microspheres formation, as well as raising the visible light-induced photocatalytic activity of the photocatalysts. Longer reaction time was also accompanied by an increase in the efficiency of 2,3,5-triphenyltetrazolium chloride decomposition. The properties of the photocatalysts were investigated by means of UV-VIS diffuse reflectance spectroscopy (DRS), BET surface area measurements, scanning electron microscopy (SEM), X-ray powder diffraction (XRD) analysis, and XPS.

5.
Beilstein J Nanotechnol ; 9: 580-590, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29527433

RESUMEN

To investigate the effect of the ionic liquid (IL) chain length on the surface properties and photoactivity of TiO2, a series of TiO2 microspheres have been synthesized via a solvothermal method assisted by 1-methyl-3-octadecylimidazolium chloride ([ODMIM][Cl]) and 1-methyl-3-tetradecylimidazolium chloride ([TDMIM][Cl]). All as-prepared samples were characterized by X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS), diffuse reflectance spectroscopy (DRS), scanning transmission microscopy (STEM) and the Brunauer-Emmett-Teller (BET) surface area method, whereas the photocatalytic activity was evaluated by the degradation of phenol in aqueous solution under visible light irradiation (λ > 420 nm). The highest photoefficiency (four times higher than pristine TiO2) was observed for the TiO2 sample obtained in the presence of [TDMIM][Cl] for a IL to TiO2 precursor molar ratio of 1:3. It was revealed that interactions between the ions of the ionic liquid and the surface of the growing titanium dioxide spheres results in a red-shift of absorption edge for the IL-TiO2 semiconductors. In this regard, the direct increase of the photoactivity of IL-TiO2 in comparison to pristine TiO2 was observed. The active species trapping experiments indicated that O2•- is the main active species, created at the surface of the IL-TiO2 material under visible-light illumination, and is responsible for the effective phenol degradation.

6.
Adv Colloid Interface Sci ; 256: 352-372, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29544654

RESUMEN

Quantum dot (QD)-decorated semiconductor micro- and nanoparticles are a new class of functional nanomaterials that have attracted considerable interest for their unique structural, optical and electronic properties that result from the large surface-to-volume ratio and the quantum confinement effect. In addition, because of QDs' excellent light-harvesting capacity, unique photoinduced electron transfer, and up-conversion behaviour, semiconductor nanoparticles decorated with quantum dots have been used widely in photocatalytic applications for the degradation of organic pollutants in both the gas and aqueous phases. This review is a comprehensive overview of the recent progress in synthesis methods for quantum dots and quantum dot-decorated semiconductor composites with an emphasis on their composition, morphology and optical behaviour. Furthermore, various approaches used for the preparation of QD-based composites are discussed in detail with respect to visible and UV light-induced photoactivity. Finally, an outlook on future development is proposed with the goal of overcoming challenges and stimulating further research into this promising field.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA