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1.
Angew Chem Int Ed Engl ; 63(19): e202401818, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38465851

RESUMEN

Magnesium (Mg) batteries hold promise as a large-scale energy storage solution, but their progress has been hindered by the lack of high-performance cathodes. Here, we address this challenge by unlocking the reversible four-electron Te0/Te4+ conversion in elemental Te, enabling the demonstration of superior Mg//Te dual-ion batteries. Specifically, the classic magnesium aluminum chloride complex (MACC) electrolyte is tailored by introducing Mg bis(trifluoromethanesulfonyl)imide (Mg(TFSI)2), which initiates the Te0/Te4+ conversion with two distinct charge-storage steps. Te cathode undergoes Te/TeCl4 conversion involving Cl- as charge carriers, during which a tellurium subchloride phase is presented as an intermediate. Significantly, the Te cathode achieves a high specific capacity of 543 mAh gTe -1 and an outstanding energy density of 850 Wh kgTe -1, outperforming most of the previously reported cathodes. Our electrolyte analysis indicates that the addition of Mg(TFSI)2 reduces the overall ion-molecule interaction and mitigates the strength of ion-solvent aggregation within the MACC electrolyte, which implies the facilized Cl- dissociation from the electrolyte. Besides, Mg(TFSI)2 is verified as an essential buffer to mitigate the corrosion and passivation of Mg anodes caused by the consumption of the electrolyte MgCl2 in Mg//Te dual-ion cells. These findings provide crucial insights into the development of advanced Mg-based dual-ion batteries.

2.
Chem Biol Interact ; 376: 110444, 2023 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-36906140

RESUMEN

Due to its high surface area and convenient functionalization, graphene oxide has many potential applications in biomedicine, especially as a drug carrier. However, knowledge about its internalization inside mammalian cells is still limited. Graphene oxide cellular uptake is a complex phenomenon affected by factors such as the size of the particle and modifications of its surface. Moreover, nanomaterials introduced into living organisms interact with biological fluids' components. It may further alter its biological properties. All these factors must be considered when the cellular uptake of potential drug carriers is considered. In this study, the effect of graphene oxide particle sizes on internalization efficiency into normal (LL-24) and cancerous (A549) human lung cells was investigated. Moreover, one set of samples was incubated with human serum to determine how the interaction of graphene oxide with serum components affects its structure, surface, and interaction with cells. Our findings indicate that samples incubated with serum enhance cell proliferation but enter the cells with lesser efficiency than their counterparts not incubated with human serum. What is more affinity towards the cells was higher for larger particles.


Asunto(s)
Grafito , Nanoestructuras , Animales , Humanos , Grafito/química , Pulmón , Nanoestructuras/química , Portadores de Fármacos , Mamíferos
3.
Crit Rev Anal Chem ; : 1-23, 2023 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-37083454

RESUMEN

The review presents methods that are used frequently for multi-analytical study of fossil resins. The preliminary characterization relies on physical methods such as microhardness, density and fluorescence in UV light measurements. The spectroscopic methods: infrared spectroscopy, Raman spectroscopy, fluorescence spectroscopy are also presented in the paper. Besides that, the review also contains examples of the application of chromatographic methods: gas chromatography, thin layer chromatography, high-performance liquid chromatography, two-dimensional gas chromatography coupled to time-of-flight mass spectrometry as well as sample preparation methods for chromatographic studies such as pyrolysis. Additionally, thermal methods such as thermogravimetric analysis and differential scanning calorimetry also are covered by the review. Beside the examples of application, a detailed description with development history and perspective for further improvement are presented for each method. Moreover, fit-for-purpose assessment of each method is illustrated based on many examples from literature. The paper also contains examples of the application of multivariate statistical analysis and chemometric methods for comparing multiple properties of different fossil resin specimens for differentiation and classification purposes.

4.
Materials (Basel) ; 16(1)2022 Dec 27.
Artículo en Inglés | MEDLINE | ID: mdl-36614605

RESUMEN

The introduction of the hydrogen economy, despite its obvious technological problems, creates a need for a significant number of niche-focused solutions, such as small-sized (10-100 W) fuel cells able to run on hydrogen of lesser purity than what is considered a standard in the case of PEMFCs. One of the solutions can be derived from the fact that an increase in the operational temperature of a cell significantly decreases its susceptibility to catalyst poisoning. Electrolytes suitable for the so-called medium temperature operational range of 120-400 °C, hence developed, are neither commercialized nor standardized. Among them, phosphate silicate protonically conductive glasses were found not only to reveal interestingly high levels of operational parameters, but also, to exhibit superior chemical and electrochemical stability over their polymeric counterparts. On the other hand, their mechanical properties, including cracking fragility, still need elaboration. Initial studies of the composite phosphate silicate glasses with uranyl-based protonic conductors, presented here, proved their value both in terms of application in fuel cell systems, and in terms of understanding the mechanism governing the charge transport mechanism in these and similar systems. It was found that whereas systems containing 10-20 wt% of the crystalline additive suffer from significant instability, materials containing 45-80 wt% (with an optimum at 60%) should be examined more thoughtfully. Moreover, the uranyl hydrogen phosphate was found to surpass its arsenate counterpart as an interesting self-healing behavior of the phase structure of the derived composite was proved.

5.
Phys Chem Chem Phys ; 13(23): 11136-47, 2011 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-21562676

RESUMEN

Molecular level interactions are of crucial importance for the transport properties and overall performance of ion conducting electrolytes. In this work we explore ion-ion and ion-solvent interactions in liquid and solid polymer electrolytes of lithium 4,5-dicyano-(2-trifluoromethyl)imidazolide (LiTDI)-a promising salt for lithium battery applications-using Raman spectroscopy and density functional theory calculations. High concentrations of ion associates are found in LiTDI:acetonitrile electrolytes, the vibrational signatures of which are transferable to PEO-based LiTDI electrolytes. The origins of the spectroscopic changes are interpreted by comparing experimental spectra with simulated Raman spectra of model structures. Simple ion pair models in vacuum identify the imidazole nitrogen atom of the TDI anion to be the most important coordination site for Li(+), however, including implicit or explicit solvent effects lead to qualitative changes in the coordination geometry and improved correlation of experimental and simulated Raman spectra. To model larger aggregates, solvent effects are found to be crucial, and we finally suggest possible triplet and dimer ionic structures in the investigated electrolytes. In addition, the effects of introducing water into the electrolytes-via a hydrate form of LiTDI-are discussed.

6.
Front Chem ; 9: 665205, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34164377

RESUMEN

Graphene oxide-silver nanoparticle nanohybrids were synthesized by simple reduction of the silver nitrate and graphene oxide (GO) mixture in water using the mild reducing agent ascorbic acid. The concentration of ascorbic acid was varied to verify the possible influence of the GO surface composition on the efficiency of the hybrid material as substrates for surface enhanced Raman spectroscopy (SERS). Furthermore, the composites were conditioned in ammonia solution or in potassium hydroxide diluted solution. For comparison, the graphene oxide-silver nanoparticle composite has been synthesized using the ammonia-treated GO. All materials were characterized using spectroscopic and microscopic methods including UV-Vis, infrared, and Raman spectroscopy and scanning electron microscopy. The SERS efficiency of the nanohybrids was tested using 4-aminothiophenol (PATP). The optimal synthesis conditions were found. Ammonia and potassium peroxide drop-casted on the composite changed the SERS properties. The sample treated with KOH showed the best SERS enhancement. The variation of the SERS enhancement was correlated with the shape of the UV-Vis characteristics and the surface structure of the composites.

7.
J Phys Chem A ; 114(6): 2324-30, 2010 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-20092259

RESUMEN

Benzoxaboroles possessing aryl substituents in the oxaborole ring were synthesized, and their structures were determined by single-crystal X-ray diffraction. Structures in the solid state are centrosymmetric dimers with two intermolecular hydrogen bonds. These compounds were investigated using a combination of the spectroscopic and the computational approach, comparing their properties with the unsubstituted compound. Investigated compounds were characterized by (1)H, (13)C, and (11)B NMR spectroscopy in solution. Assignment of (1)H and (13)C signals was made on the basis of HSQC and HMBC spectra. The molecular structure of 1,3-dihydro-1-hydroxy-3-phenyl-2,1-benzoxaborole was calculated by the density functional (B3LYP) method with the extended 6-311++G(d,p) basis set. The calculated geometrical parameters were compared with experimental X-ray data, and the differences between experimental and calculated values were found to be of the order of experiment standard deviation, confirming a good description by this level of theory. The harmonic frequencies, potential energy distribution (PED), and IR intensities of this compound and its deuterated analogue were calculated with the B3LYP method. The assignment of the experimental spectra was made on the basis of the calculated PED. The consequence of dimer formation is the splitting of the vibrational modes into symmetric and antisymmetric vibrations. The structure modification resulting from the hydrogen bonded dimers formation is presented.


Asunto(s)
Compuestos de Boro/química , Compuestos Bicíclicos Heterocíclicos con Puentes/química , Compuestos de Boro/síntesis química , Compuestos Bicíclicos Heterocíclicos con Puentes/síntesis química , Simulación por Computador , Cristalografía por Rayos X , Espectroscopía de Resonancia Magnética , Modelos Moleculares , Estructura Molecular
8.
Sensors (Basel) ; 10(5): 4926-49, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-22399915

RESUMEN

Metal artworks are subjected to corrosion and oxidation processes due to reactive agents present in the air, water and in the ground that these objects have been in contact with for hundreds of years. This is the case for archaeological metals that are recovered from excavation sites, as well as artefacts exposed to polluted air. Stabilization of the conservation state of these objects needs precise diagnostics of the accrued surface layers and identification of original, historical materials before further protective treatments, including safe laser cleaning of unwanted layers. This paper presents analyses of the chemical composition and stratigraphy of corrosion products with the use of laser induced breakdown spectroscopy (LIBS) and Raman spectroscopy. The discussion of the results is supported by material studies (SEM-EDS, XRF, ion-analyses). The tests were performed on several samples taken from original objects, including copper roofing from Wilanów Palace in Warsaw and Karol Poznanski Palace in LódY, bronze decorative figures from the Wilanów Palace gardens, and four archaeological examples of old jewellery (different copper alloys). Work has been performed as a part of the MATLAS project in the frames of EEA and Norway Grants (www.matlas.eu) and the results enable the comparison of the methodology and to elaborate the joint diagnostic procedures of the three project partner independent laboratories.

9.
J Vet Res ; 64(2): 305-312, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32587919

RESUMEN

INTRODUCTION: Differing conditions in captive breeding and in the wild have impact on the mineral profile of the pheasant carcass and its heavy metal contents. This may be an indicator of environmental contamination. The study evaluated the nutritional composition and selected macro- and trace element contents (heavy metals in particular) in usable sections of pheasant breast and thigh muscles originating from captive breeding and wild birds. MATERIAL AND METHODS: The tests were performed on the breast and thigh muscles of 20 wild and 20 farm bred birds from around Lublin, Poland, with equal sex representation. The nutrient and lead, cadmium, chromium, and nickel contents were determined using inductively-coupled plasma atomic emission spectroscopy. RESULTS: The farmed pheasants had a higher proportion of breast muscle. The thigh muscles of all birds had a higher fat content than the breast muscles (5.1 g vs. 3.4 g per kg of natural weight). The macroelement level depended on the muscle type and bird origin. The trace element content also did and gender dependence was also evident. The wild birds contained more cadmium in the breast muscles and lead in both muscles than the farm-raised ones. CONCLUSION: The high quality and usefulness of wild and farmed pheasant meat is confirmed. It has advantageous macro- and trace element contents and permissible heavy metal contents except for lead in wild birds. The heavy metal level can be a bioindicator of their environmental occurrence. In wild birds, the lead level may also reflect birdshot remnants.

10.
J Phys Chem B ; 113(19): 6682-91, 2009 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-19361175

RESUMEN

Thin films of a new composite of an electroactive fullerene-based (C60-Pd) polymer and HiPCO single-wall carbon nanotubes, which were noncovalently modified by 1-pyrenebutiric acid (pyr-SWCNTs), were electrochemically prepared under multiscan cyclic voltammetry conditions. With respect to blank polymer, superior conductive, capacitive, and viscoelasitic properties of the composite were demonstrated. Composition of pyr-SWCNTs was determined by thermogravimetric analyses, which showed one molecule of 1-pyrenebutiric acid per approximately 20 carbon atoms of SWCNT. Atomic force microscopy imaging revealed that pyr-SWCNTs form tangles of pyr-SWCNTs bundles surrounded by globular clusters of the C60-Pd polymer. Peaks characteristic of both pyr-SWCNTs (radial breathing modes at approximately 200 to 300 cm(-1)) and C60-Pd polymer in the Raman spectra recorded for the composite confirmed the presence of pyr-SWCNTs in the composite film. The mass of the deposited film was in situ measured by piezoelectric microgravimetry with the use of an electrochemical quartz crystal microbalance (EQCM). Then, curves of the current, resonant frequency change, and dynamic resistance change versus the potential in different potential ranges were simultaneously recorded in a blank acetonitrile solution of tetrabutylammonium perchlorate. Specific capacitance, determined at -1.20 V for the composite as 90 F g(-1), was twice as high as that for the polymer. Electrochemical impedance spectroscopy was used to determine impedance parameters of both the C60-Pd polymer and C60-Pd/pyr-SWCNTs composite film. This data analysis indicated increased capacitance and decreased resistance for the new composite film.

11.
Environ Sci Pollut Res Int ; 25(31): 31101-31112, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30187410

RESUMEN

Environmental management of cellulose production waste and municipal sewage sludge appears to be substantiated due to various physicochemical properties of these wastes. The aim of the conducted research was to determine the effect of cellulose production waste and sewage sludge on yielding and heavy metal uptake by a plant mixture. The research was conducted under field experiment conditions, determining the fertilizer value of these wastes in the environmental aspect. The research was carried out in the years 2013-2016. Species composition of the plant mixture was adjusted to habitat conditions. It was established that, as compared with the cellulose production waste, the municipal sewage sludge used in the experiment had a higher content of macroelements. The content of heavy metals in the studied waste did not exceed the limits that condition their use in agriculture and reclamation. Applying only the cellulose production waste did not significantly decrease the yield of the plants. Municipal sewage sludge showed the highest yield-forming effect. Mixing the above-mentioned wastes and their application to soil had a significant effect on the increase in the plant mixture yield. The waste applied to soil also increased the content of Cr, Cd, Pb, Cu, and Zn in the plant mix. The level of heavy metal content in the plant mix did not exclude this biomass from being used for fodder or reclamation purposes. The cellulose production waste and municipal sewage sludge increased the heavy metal uptake by the plant mixture. The plant biomass extracted heavy metals from the sewage sludge more intensively than from the cellulose production waste. Among the analyzed heavy metals, the highest phytoremediation was recorded for Ni (30%), followed by Cd (20%), Cr (15%), Pb (10%), and the lowest for Cu (9%) and Zn (8%). Application of the cellulose production waste and sewage sludge to soil also increased the content of the studied heavy metals in soil. However, it did not cause deterioration of soil quality standards. Heterogeneity in the chemical composition of the wastes confirms that each batch intended to be used for environmental management should be subjected to chemical control.


Asunto(s)
Celulosa , Fertilizantes , Metales Pesados/metabolismo , Plantas/metabolismo , Aguas del Alcantarillado , Contaminantes del Suelo/metabolismo , Residuos , Agricultura , Biodegradación Ambiental , Biomasa
12.
Talanta ; 179: 784-791, 2018 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-29310308

RESUMEN

Multilayered fragments of murals were used to evaluate the usefulness of two laser-based instrumental methods: laser induced breakdown spectroscopy (LIBS) and laser ablation (LA) inductively coupled plasma mass spectrometry (ICP-MS) for elemental imaging of unique historic samples. Simultaneous LA/LIBS measurements with the use of 266nm Nd:YAG laser were performed on cross-sections of mediaeval Nubian objects with specific blue painting layers including either Egyptian blue (CaCuSi4O10) or lapis lazuli (Na8-10Al6Si6O24S2-4). A combined use of both laser-based methods allowed for clear distinguishing of blue pigments based on visual imaging of a chemical composition of heterogeneous archaeological inorganic samples. The identification of the pigments was confirmed with Raman spectroscopy.

13.
Sci Rep ; 7: 40036, 2017 01 09.
Artículo en Inglés | MEDLINE | ID: mdl-28067301

RESUMEN

A new family of fluorine-free solid-polymer electrolytes, for use in sodium-ion battery applications, is presented. Three novel sodium salts withdiffuse negative charges: sodium pentacyanopropenide (NaPCPI), sodium 2,3,4,5-tetracyanopirolate (NaTCP) and sodium 2,4,5-tricyanoimidazolate (NaTIM) were designed andtested in a poly(ethylene oxide) (PEO) matrix as polymer electrolytes for anall-solid sodium-ion battery. Due to unique, non-covalent structural configurations of anions, improved ionic conductivities were observed. As an example, "liquid-like" high conductivities (>1 mS cm-1) were obtained above 70 °C for solid-polymer electrolyte with a PEO to NaTCP molar ratio of 16:1. All presented salts showed high thermal stability and suitable windows of electrochemical stability between 3 and 5 V. These new anions open a new class of compounds with non-covalent structure for electrolytes system applications.

14.
Chem Commun (Camb) ; 51(65): 12985-8, 2015 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-26176023

RESUMEN

A novel synthesis method for the preparation of Cu2ZnSnS4 nanocrystals is presented using a liquid precursor of tin, namely tin(II) 2-ethylhexanoate, which yields small and nearly monodisperse NCs either in the kesterite or in the wurtzite phase depending on the sulfur source (elemental sulfur in oleylamine vs. dodecanethiol).

15.
J Chem Phys ; 128(12): 124512, 2008 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-18376948

RESUMEN

Boronic acids have emerged as one of the most useful class of organoboron molecules, with application in synthesis, catalysis, analytical chemistry, supramolecular chemistry, biology, and medicine. In this study, the structural and spectroscopic properties of n-butylboronic acid were investigated using experimental and theoretical approaches. X-ray crystallography method provided structural information on the studied compound in the solid state. Infrared and Raman spectroscopy served as tools for the data collection on vibrational modes of the analyzed system. Car-Parrinello molecular dynamics simulations in solid state were carried out at 100 and 293 K to investigate an environmental and temperature influence on molecular properties of the n-butylboronic acid. Analysis of interatomic distances of atoms involved in the intermolecular hydrogen bond was performed to study the proton motion in the crystal. Subsequently, Fourier transform of autocorrelation functions of atomic velocities and dipole moment was applied to study the vibrational properties of the compound. In addition, the inclusion of quantum nature of proton motion was performed for O-H stretching vibrational mode by application of the envelope method for intermolecular hydrogen-bonded system. The second part of the computational study consists of simulations performed in vacuo. Monomeric and dimeric forms of the n-butylboronic acid were investigated using density functional theory and Moller-Plesset second-order perturbation method. The basis set superposition error was estimated. Finally, atoms in molecules (AIM) theory was applied to study electron density topology and properties of the intermolecular hydrogen bond. Successful reproduction of the molecular properties of the n-butylboronic acid by computational methodologies, presented in the manuscript, indicates the way for future studies of large boron-containing organic systems of importance in biology or materials science.


Asunto(s)
Compuestos de Boro/química , Simulación por Computador , Modelos Químicos , Teoría Cuántica , Espectrometría Raman/métodos , Cristalografía por Rayos X , Enlace de Hidrógeno , Modelos Moleculares , Estructura Molecular , Protones , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Factores de Tiempo , Vibración
16.
Anal Chim Acta ; 575(1): 144-50, 2006 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-17723584

RESUMEN

Two methods have been used for examination of transport of charge in gels soaked with DMF and containing dissolved polyoxometallates. The first method is based on the analysis of both Cottrellian and steady-state currents and therefore is capable of giving the concentration of the electroactive redox centres and their transport (diffusion-type) coefficient. The second method provides the real diffusion coefficients, i.e. transport coefficients free of migrational influence, for both the substrate and the product of the electrode reaction. Several gels based on poly(methyl methacrylate), with charged (addition of 1-acrylamido-2-methyl-2-propanesulphonic acid to the polymerization mixture) and uncharged chains, have been used in the investigation. The ratio obtained for the diffusion coefficient (second method) and transport coefficient (first method) was smaller for the gels containing charged polymer chains than for the gels with uncharged chains. In part these changes could be explained by the contribution of migration to the transport of polyoxomatallates in the gels. However, the impact of the changes in the polymer-channel capacity at the electrode surface while the electrode process proceeds was also considered. These structural changes should affect differently the methods based on different time domains.

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