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Real-time Analysis for Pollution Prevention
Published in Aidé Sáenz-Galindo, Adali Oliva Castañeda-Facio, Raúl Rodríguez-Herrera, Green Chemistry and Applications, 2020
Maria Isabel Martinez Espinoza
Infrared/Near-infrared Spectroscopy (IR/NIR). Infrared spectroscopy is a non-destructive technique that offers several advantages such as the use of a small sample quantity, high sensitivity and can be used directly on the sample without any treatment. These features allow real-time monitoring without generating any residue, low cost, fast and easy to use and for this reason are considered a green analytical technique. To date there are several devices including portable ones, which eliminates the need for sampling and allows measuring in the field or directly in the process through different probes. Both IR and NIR are techniques used in industry for continuous monitoring of the emission of gas and particles, in the biomedical and pharmaceutical area for the monitoring of biomolecules and natural compounds (Vanarase et al., 2010).
Resin-Based Composites in Dentistry—A Review
Published in S. M. Sapuan, Y. Nukman, N. A. Abu Osman, R. A. Ilyas, Composites in Biomedical Applications, 2020
Z. Radzi, R. A. Diab, N. A. Yahya, M. A. G. Gonzalez
These methods provide a direct approach to determine the effectiveness of cure by measuring the DC (Asmussen, 1982b; Eliades, Vougiouklakis, & Caputo, 1987; Ferracane & Greener, 1984; Rueggeberg & Craig, 1988). This is achieved by measuring both the percentage of carbon-carbon single bonds in the cured material and the percentage of unreacted C=C bonds. Vibrational spectroscopy can be classified into two techniques. The first technique is Fourier transform infrared spectroscopy (FTIR), which is sometimes documented as IR spectroscopy and is based on light absorption. The second technique, Raman spectroscopy is based on light scattering (Figure 4.7). Two devices are popularly used: Fourier transform-Raman spectroscopy (FT-Raman) and micro-Raman spectroscopy (MRS) (De Santis & Baldi, 2004). Other available techniques include differential thermal analysis (DTA), differential scanning calorimetry (DSC), and nuclear magnetic resonance (NMR) (Alshihri, Santini, & Aldossary, 2018).
Sample Handling in Infrared Spectroscopy — An Overview
Published in Patricia B. Coleman, Practical Sampling Techniques for INFRARED ANALYSIS, 2020
Infrared Spectroscopy is a particularly useful analytical technique because of its enormous versatility. Spectra can be obtained, often nondestructively, on samples in all three states of matter — gases, liquids, and solids. For a given sample, there will usually be at least two or three, and sometimes as many as four or five, different sampling techniques that can be used in obtaining the spectrum, thus permitting the spectroscopist a choice that may be dictated by available accessory equipment, personal preference, or the detailed nature of that particular sample. In this chapter, we will present a broad overview of the various techniques for sample handling. Subsequent chapters in this book will deal in detail with a number of specific procedures.
Looking at ancient objects under a different light: cultural heritage science at Elettra
Published in Radiation Effects and Defects in Solids, 2022
Matteo Amati, Alessandra Gianoncelli, Emanuel Karantzoulis, Barbara Rossi, Lisa Vaccari, Franco Zanini
Among the characterisation techniques considered in this contribution, infrared spectroscopy deals with radiation of longer wavelengths and lower energetic content: the infrared light. Infrared radiation (IR) extends from the nominal red edge of the visible spectrum to microwaves, a spectral range conventionally described by three regions, near-infrared (between 14,000 and 4000 cm−1), mid-infrared (between 4000 and 400 cm−1) and far-infrared (between 400 and 10 cm−1) depending on their relation to visible light. Infrared spectroscopy encompasses a broad range of techniques, mostly based on absorption spectroscopy: infrared light absorbed by a molecule induces molecular transitions to excited vibro-rotational states, at frequencies that are characteristic of the molecule, primarily through the mass of covalently bonded atoms and the strength of their linkage. Fundamental vibrations are excited by mid-IR light, while vibrational overtones and combination bands are in the near-IR, and rotational details are searchable in the far-IR. All over, infrared spectroscopy provides qualitative and, in controlled conditions, quantitative information on the chemical moieties constituting a molecule, in a safer manner, being IR nonionising and without suffering from the fluorescence effects that often limit both visible and UV Raman spectroscopy.
Evaluating the role of recycling rate and rejuvenator on the chemo-rheological properties of reclaimed polymer-modified binders
Published in Road Materials and Pavement Design, 2021
Alexandros Margaritis, Georgios Pipintakos, Geert Jacobs, David Hernando, Mats Bruynen, Jeroen Bruurs, Wim Van den bergh
The attenuated total reflectance Fourier-transform infrared spectroscopy (ATR-FTIR) analysis method is a technique that uses infrared light to observe changes in chemical bonds. In this study, the test was performed taking 32 repetitive scans on a binder sample using a Thermo Fisher Scientific Nicolet iS™ 10 spectrometer. The scans were performed with a resolution of 4 cm−1 in a range between 4000 and 400 cm−1. The average of the 32 scans yields a spectrum that is normalised before analysis. The normalisation procedure is based on the methods described in previous studies (Hofko et al., 2018; Margaritis et al., 2020): first, the spectra are shifted to an absorbance of 0 at 1753 cm−1. Then, the spectra are scaled to an absorbance of 1 at 2923 cm−1.
Effect of rejuvenator addition location in plant on mechanical and chemical properties of RAP binder
Published in International Journal of Pavement Engineering, 2020
Martins Zaumanis, Maria Chiara Cavalli, Lily D. Poulikakos
In order to characterise chemical changes in the binders as a result of oxidation due to ageing, ATR-FTIR was used. Infrared spectroscopy measures the infrared light absorbed by bonds in molecules when the infrared light has the same frequency as the vibration frequency of the bonds, enabling identification of chemical functionalities corresponding to the different bonds/functional groups, as a function of the wavenumber. The intensity of the peaks is a function of the concentration of the bonds/functional groups. In the case of ageing in bitumen, such as in RAP, it is well established that changes in the intensity of the spectral peaks corresponding to carbonyl and sulphoxide functional groups are relevant ageing indicators (Petersen and Glaser 2011, Poulikakos et al. 2014a, Poulikakos et al. 2014b).