21 research outputs found

    Dataset on broadband electrochemical impedance spectroscopy of Lithium-Ion batteries for different values of the state-of-charge

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    This dataset consists of electrochemical impedance spectroscopy measurements on commonly-used batteries, namely Samsung ICR18650-26J cylindrical Lithium-Ion cells. The complex impedance of the batteries was measured at a set of fourteen different frequencies from 0.05 Hz to 1000 Hz, using a random-phase multi-sine excitation signal. For each excited frequency, the current amplitude was 50 mA, resulting in a measurement uncertainty of approximately 0.1 mΩ. Six measurement repetitions are provided at ten different states-of-charge of four different brand-new batteries. Repeated EIS measurement results were obtained, for each individual battery cell, from six separate discharge cycles. All measurements were performed with the battery placed in a temperature-controlled chamber at 25 ± 1 °C. Batteries were allowed to thermalize before each measurement

    Structural characterization of major soyasaponins in traditional cultivars of Fagioli di Sarconi beans investigated by high-resolution tandem mass spectrometry

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    Major soyasaponins, i.e., soyasaponins I, V, βg, and αg from traditional Fagioli di Sarconi beans (Phaseolus vulgaris L., ecotype Tabacchino), were analyzed by reversed-phase liquid chromatography-mass spectrometry (MS) using high-resolution Fourier transform ion cyclotron resonance (FTICR) MS on electrospray ionization in positive-ion mode. Fagioli di Sarconi beans are protected by the European Union [Commission Regulation (EC) No 1263/96] with the mark PGI (for "Protected Geographical Indication"), and are cultivated in Basilicata (southern Italy). Protonated adducts of soyasaponins I, V, βg, and αg were observed at m/z 943.5262, 959.5213, 1069.5583, and 1085.5534, respectively. Gas-phase dissociation of soyasaponins by infrared multiphoton dissociation FTICR MS was performed using a CO2 laser source at a wavelength of 10.6 μm. Most of the fragment ions were identified unambiguously by using the high-resolution and accurate mass value provided by the FTICR mass spectrometer. All soyasaponins exhibit a sequential and neutral loss of sugar moieties at relatively short irradiation times (i.e., less than 50 ms). When the pulse length was increased, a more pronounced fragmentation occurred, with several signals in the lower part of the mass spectrum. In the case of soyasaponins βg and αg, the occurrence of the conjugated product ion at m/z 127.0389 ([C6H6O3+H]+, 2,3-dihydro-2, 5-dihydroxy-6-methyl-4H-pyran-4-one) was evidenced. Coupling reversed-phase liquid chromatography with high-performance FTICR MS in combination with infrared multiphoton dissociation tandem MS proved to be very promising for the structural characterization of soyasaponins, and is also suitable for the rapid and accurate structural investigation of other saponins

    Structural characterization of arginine-vasopressin and lysine-vasopressin by Fourier-transform ion cyclotron resonance mass spectrometry and infrared multiphoton dissociation.

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    Arginine-vasopressin (AVP) and lysine-vasopressin (LVP) were analyzed by reversed-phase liquid chromatography/mass spectrometry (LC-MS) using Fourier-transform ion cyclotron resonance (FT-ICR) mass spectrometry (MS) electrospray ionization (ESI) in the positive ion mode. LVP and AVP exhibited the protonated adduct [M+H](+) as the predominant ion at m/z 1056.43965 and at m/z 1084.44561, respectively. Infrared multiphoton dissociation (IRMPD), using a CO2 laser source at a wavelength of 10.6μm, was applied to protonated vasopressin molecules. The IRMPD mass spectra presented abundant mass fragments essential for a complete structural information. Several fragment ions, shared between two target molecules, are discussed in detail. Some previously unpublished fragments were identified unambiguously utilizing the high resolution and accurate mass information provided by the FT-ICR mass spectrometer. The opening of the disulfide loop and the cleavage of the peptide bonds within the ring were observed even under low-energy fragmentation conditions. Coupling the high-performance FT-ICR mass spectrometer with IRMPD as a contemporary fragmentation technique proved to be very promising for the structural characterization of vasopressin

    LiBEIS : A software tool for broadband electrochemical impedance spectroscopy of lithium-ion batteries[Formula presented]

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    Electrochemical impedance spectroscopy (EIS) is a fundamental tool used in numerous research fields and applications. In particular, EIS is commonly employed for studying and monitoring lithium-ion batteries, to ensure their safe and efficient operation. The LiBEIS software tool computes EIS data by processing the voltage and current time series acquired from a battery under test, which is excited with a broadband current signal. Furthermore, LiBEIS performs fitting of the EIS data to an equivalent circuit model, which is often employed in practice to analyse the behaviour of the battery. Finally, LiBEIS implements exploratory data analysis tools and machine-learning methods aimed at estimating the state-of-charge (SOC) from EIS data

    Determination of soyasaponins in Fagioli di Sarconi beans (Phaseolus vulgaris L.) by LC-ESI-FTICR-MS and evaluation of their hypoglycemic activity.

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    Soyasaponins are oleanene-type triterpenoid saponins, naturally occurring in many edible plants that have attracted a great deal of attention for their role in preventing chronic diseases. The aim of this study was to establish the distribution and the content of soyasaponins in 21 ecotypes of Fagioli di Sarconi beans (Phaseolus vulgaris, Leguminosae). High-performance reversed-phase liquid chromatography (RPLC) with positive electrospray ionization (ESI(+)) and Fourier transform ion cyclotron resonance (FTICR) mass spectrometry (MS) in conjunction with infrared multiphoton dissociation (IRMPD) was applied for the unambiguous identification of soyasaponins Ba (m/z 959.5213, [C48H79O19](+)), Bb (m/z 943.5273, [C48H79O18](+)), Bd (m/z 957.5122, [C48H77O19](+)), and Be (m/z 941.5166, [C48H77O18](+)), which are the only commercially available reference standards. In addition, the several diagnostic product ions generated by IRMPD in the ICR-MS cell allowed us the putative identification of soyasaponins Bb' (m/z 797.4680, [C42H69O14](+)), alpha g (m/z 1085.5544, [C54H85O22](+)), beta g (m/z 1069.5600, [C54H85O21](+)), and gamma g (m/z 923.5009, [C48H75O17](+)), establishing thus their membership in the soyasaponin group. Quantitative and semiquantitative analysis of identified soyasaponins were also performed by RPLC-ESI(+) FTICR-MS; the total concentration levels were found ranging from 83.6 +/- 9.3 to 767 +/- 37 mg/kg. In vitro hypoglycemic outcomes of four soyasaponin standards were evaluated; significant inhibitory activities were obtained with IC50 values ranging from 1.5 +/- 0.1 to 2.3 +/- 0.2 mu g/mL and 12.0 +/- 1.1 to 29.4 +/- 1.4 mu g/mL for alpha-glucosidase and alpha-amylase, respectively. This study represents the first detailed investigation on the antidiabetic activity of bioactive constituents found in Fagioli di Sarconi beans

    REMOVAL OF BTEX FROM WATER BY SUPER-EXPANDED GRAPHITE

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    Nanotechnologies and nanomaterials are the most promising technological frontier in the field of water protection in terms of high efficiency and environmental performances. Among them, graphene-based materials attracted a lot of interest during the last years. Graphene is the main building block of all graphite materials. It is a single sheet of carbon atoms contained in a 2D honeycomb lattice. The possibilities of technological applications of graphene-based materials are derived from some of their peculiar features such as high specific surface area, exceptional electrical conductivity and electron mobility. Expanded graphite is a graphene-based material deriving from graphite flakes expansion, which attracted a great interest in oil adsorption from water during the last ten years. A super-expanded graphite, with an apparent density down to 2.3 g/l, is characterized by highly crystalline nature that guarantees a thermal stability of the material up to 600°C in air and provides a hydrophobic behavior. Great efforts have been made in the last years to modify the water technologies for removing BTEX compounds from contaminated water. Although different methods have been used for BTEX removal from water, each of them possesses some limitations. Therefore a search of novel effective methods for water purification from BTEX compounds is still of recent interest. In this paper, we focus on the investigation of the adsorptive properties towards BTEX of super-expanded graphite

    Perchè continuare il percorso in SCI al termine dell'esperienza accademica?

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    L'importanza di appartenere ad una societĂ  scientifica va al di lĂ  del fatto di lavorare in accademia o industria
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