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471.
Andrew D. Cutler Emanuela C. A. Gallo Luca M. L. Cantu 《Journal of Raman spectroscopy : JRS》2016,47(4):416-424
WIDECARS measures temperature and mole fractions of most of the major species in ethylene–air flames. One of the issues in implementing this technique is fitting the experimental spectra to theory to obtain flame conditions (temperature, species mole fractions). Individual spectra contain many species resonances, and theory is slow to compute. Libraries of precalculated spectra can be used, but a library of sufficient density for accurate interpolation is large given the many variables. A new fitting algorithm is presented which utilizes a less‐dense library, and additional spectra are calculated during fitting to maintain accuracy. The iterative convergence method converts the problem of minimizing fit error, which converges slowly, to a zero finding problem, which converges reliably, rapidly, and accurately to best fit. Various practical fitting issues, such as the effects of dye laser mode noise and variability, phase‐matching efficiency, and shifts of the spectrum on the spectrometer are addressed. The technique is demonstrated in the analysis of experimental measurements in an equivalence ratio 2.1 ethylene–air flame above the surface of a McKenna burner. Precision errors because of experimental and fitting effects are discussed. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
472.
Patrizio Vaiano Benito Carotenuto Marco Pisco Armando Ricciardi Giuseppe Quero Marco Consales Alessio Crescitelli Emanuela Esposito Andrea Cusano 《Laser \u0026amp; Photonics Reviews》2016,10(6):922-961
This review presents an overview of “Lab on Fiber” technologies and devices with special focus on the design and development of advanced fiber optic nanoprobes for biological applications. Depending on the specific location where functional materials at micro and nanoscale are integrated, “Lab on Fiber Technology” is classified into three main paradigms: Lab on Tip (where functional materials are integrated onto the optical fiber tip), Lab around Fiber (where functional materials are integrated on the outer surface of optical fibers), and Lab in Fiber (where functional materials are integrated within the holey structure of specialty optical fibers). This work reviews the strategies, the main achievements and related devices developed in the “Lab on Fiber” roadmap, discussing perspectives and challenges that lie ahead, with special focus on biological sensing applications.
473.
Francesca Pescosolido Luca Montaina Rocco Carcione Sara Politi Roberto Matassa Felicia Carotenuto Stefania Annarita Nottola Paolo Di Nardo Emanuela Tamburri 《Macromolecular bioscience》2023,23(11):2300132
Conductive hybrid xanthan gum (XG)–polyaniline (PANI) biocomposites forming 3D structures able to mimic electrical biological functions are synthesized by a strong-acid free medium. In situ aniline oxidative chemical polymerizations are performed in XG water dispersions to produce stable XG–PANI pseudoplastic fluids. XG–PANI composites with 3D architectures are obtained by subsequent freeze-drying processes. The morphological investigation highlights the formation of porous structures; UV–vis and Raman spectroscopy characterizations assess the chemical structure of the produced composites. I–V measurements evidence electrical conductivity of the samples, while electrochemical analyses point out their capability to respond to electric stimuli with electron and ion exchanges in physiological-like environment. Trial tests on prostate cancer cells evaluate biocompatibility of the XG–PANI composite. Obtained results demonstrate that a strong acid-free route produces an electrically conductive and electrochemically active XG–PANI polymer composite. The investigation of charge transport and transfer, as well as of biocompatibility properties of composite materials produced in aqueous environments, brings new perspective for exploitation of such materials in biomedical applications. In particular, the developed strategy can be used to realize biomaterials working as scaffolds that require electrical stimulations for inducing cell growth and communication or for biosignals monitoring and analysis. 相似文献
474.
Carmen Tesoro Filomena Lelario Rosanna Ciriello Giuliana Bianco Maria Assunta Acquavia Paola Montoro Maria Assunta Crescenzi Emanuela Gregori Mario Dell'Agli Stefano Piazza Antonio Guerrieri Angela Di Capua 《Journal of mass spectrometry : JMS》2023,58(10):e4952
An analytical method based on ultrasound assisted extraction (UAE) and liquid chromatography coupled to electrospray tandem mass spectrometry (LC–ESI/MS/MS) was validated and applied for determining L-dopa in four ecotypes of Fagioli di Sarconi beans (Phaseolus vulgaris L.), marked with the European label PGI (Protected Geographical Indication). The selectivity of the proposed method was ensured by the specific fragmentation of the analyte. Simple isocratic chromatographic conditions and mass spectrometric detection in multiple reaction monitoring (MRM) acquisition mode were used for sensitive quantification. The LC–ESI/MS/MS method was validated within a linear range of 0.001–5.000 μg/mL. Values of 0.4 and 1.1 ng/mL were obtained for the limits of detection and quantification, respectively. The repeatability, inter-day precision, and recovery values ranges were 0.6%–4.5%, 5.4%–9.9%, and 83%–93%, respectively. Fresh and dried beans, as well as pods, cultivated exclusively with organic methods avoiding any synthetic fertilizers and pesticides were analyzed showing an L-dopa content ranging from 0.020 ± 0.005 to 2.34 ± 0.05 μg/g dry weight. 相似文献
475.
Madison L. Williams Aghogho Abigail Olomukoro Ronald V. Emmons Nipunika H. Godage Emanuela Gionfriddo 《Journal of separation science》2023,46(23):2300571
Matrix effects can significantly impede the accuracy, sensitivity, and reliability of separation techniques presenting a formidable challenge to the analytical process. It is crucial to address matrix effects to achieve accurate and precise measurements in complex matrices. The multifaceted nature of matrix effects which can be influenced by factors such as target analyte, sample preparation protocol, composition, and choice of instrument necessitates a pragmatic approach when analyzing complex matrices. This review aims to highlight common challenges associated with matrix effects throughout the entire analytical process with emphasis on gas chromatography-mass spectrometry, liquid chromatography-mass spectrometry, and sample preparation techniques. These techniques are susceptible to matrix effects that could lead to ion suppression/enhancement or impact the analyte signal at various stages of the analytical workflow. The assessment, quantification, and mitigation of matrix effects are necessary in developing any analytical method. Strategies can be implemented to reduce or eliminate the matrix effect by changing the type of ionization, improving extraction and clean-up methods, optimization of chromatography conditions, and corrective calibration methods. While development of an effective strategy to completely mitigate matrix effects remains elusive, an integrated approach that combines sample preparation, analytical extraction, and effective instrumental analysis remains the most promising avenue for identifying and resolving matrix effects. 相似文献
476.
We present a study of molecular dynamics at the sol‐gel transition. Application of percolation and bond‐fluctuation dynamics provides critical exponents for viscoelastic properties in a strong covalent gel and shows a complex non‐exponential relaxation behaviour. The results are in good agreement with experimental findings and offer interesting pointers for discussions. 相似文献
477.
Synthesis and characterization of a new bifunctional N-heterocyclic carbene precursor with sterically expanded substituents is described. The obtained NHC is employed in the catalytic system for hydrosilylation of internal alkynes providing a fully selective and effective process in mild conditions under air. Comparison of the performance of the newly developed catalytic system with its analogs based on monofunctional NHC ligands proves that the presence of two metal atoms and the proper design of the steric environment around the metal center ensure a definitely greater activity in the hydrosilylation process. 相似文献
478.