Fluorine can negatively interfere with leach and smelting processes during mineral processing1,2. Real-time knowledge of the concentration and mineral hosts of fluorine in a mineral processing ore stream is important to protect process line equipment and product. Currently only offline methods of detection are available. Online sensors that determine specific fluorine-bearing mineral concentration

Exposing polymers to high-pressure and supercritical CO2 is a useful approach in polymer processing. Consequently, the mechanisms of polymer-polymer interaction under such conditions are worthy of further investigation. Two-dimensional (2D) correlation analysis and 2D disrelation mapping were applied to datasets of PCL(Polycaprolactone)/PLA (Poly(lactic acid)) blend with or without high-pressure CO2

Here we present an augmented form of two-dimensional correlation spectroscopy (2DCOS), that integrates in a single format data from spectroscopic and multiple non-spectroscopic sources for analysis. The integration is effected by augmenting every spectrum in a hyperspectral data set with relevant non-spectroscopic data to permit two-dimensional correlation analysis of the ensemble of augmented spectra

Characterization and quantification of individual whey proteins is crucial in many industrial dairy processes. With labor-intensive wet-chemical methods still being used as reference, a rapid quantification method for individual whey proteins is yet to be established. In this work Fourier Transform Mid-Infrared (FT-MIR) spectroscopy and Fourier Transform Near-Infrared (FT-NIR) spectroscopy were investigated

Many medical devices contain metals that interface with the body. Additionally, embedded metal fragments from military wounds are typically not removed, to avoid the risk of morbidity associated with invasive surgery. The long-term health consequences of many of these materials are not thoroughly understood. To this end, we have exposed rats for up to one year to implanted single-element metal pellets

Etalon features in infrared spectra of stratified samples, their influence on the interpretation, and methods to circumvent their presence in infrared spectra have been in discussion for decades. This paper focuses on the application of a method originally developed to remove interference fringes in the mid-infrared spectra for far-infrared Fourier transform spectroscopy on thin polymer films. We show

Many spectra have a polynomial-like baseline. Iterative polynomial fitting (IPF) is one of the most popular methods for baseline correction of these spectra. However, the baseline estimated by IPF may have substantially error when the spectrum contains significantly strong peaks or have strong peaks located at the endpoints. First, IPF uses temporary baseline estimated from the current spectrum to

The detection and measurement of hydrocarbons is of high interest for a variety of applications, for example within the oil & gas industry from extraction throughout the complete refining process, as well as for environmental monitoring and for portable safety devices. This paper presents a highly sensitive, selective and robust tunable laser analyzer that has the capability to analyze several components

Tetracycline, an animal antibiotic, may remain in milk to cause harm to human health. For economic reasons, the abuse of antibiotics is becoming more and more common. Therefore, the abuse of tetracycline has alarmed the dairy industry and many countries such as New Zealand, China and USA have proposed strict standards. Surface-Enhanced Raman Scattering (SERS) is an emerging detection method which has

The full cross-referenced details for the following companion papers appearing in the August 74[08] 2020 issue of Applied Spectroscopy were inadvertently omitted. The full reference details should instead be:

The full cross-referenced details for the following companion papers appearing in the August 74[08] 2020 issue of Applied Spectroscopy were inadvertently omitted. The full reference details should instead be:

The peroxide value (PV) of edible oils is a measure of the degree of oxidation, which directly relates to the freshness of the oil sample. Several studies previously reported in the literature have paired various spectroscopic techniques with multivariate analyses to rapidly determine PVs using field portable and process instrumentation; those efforts presented ‘best-case’ scenarios with oils from

The full color version of Table I accompanying the paper entitled, “Reporting Guidelines to Increase the Reproducibility and Comparability of Research on Microplastics”, by Win Cowger, Andy M. Booth, Bonnie M. Hamilton, Clara Thaysen, Sebastian Primpke, Keenan Munno, Amy L. Lusher, Alexandre Dehaut, Vitor P. Vaz, Max Liboiron, Lisa I. Devriese, Ludovic Hermabessiere, Chelsea Rochman, Samantha N. Athey

In this technical note, we present an advanced thermospectroscopic imager based on a Fourier transform infrared (FTIR) spectrometer and a thermal camera. This new instrument can image both thermal emission and multispectral absorbance fields in a few seconds at a resolution of 4 cm-1 or less. The setup is made of a commercial FTIR spectrometer (Thermofisher Nicolet iS50R) synchronized to an IR camera

In the present work, nanoparticles-enhanced laser-induced breakdown spectroscopy (N.E.L.I.B.S.) has been used to analyze aluminum alloy. Though LIBS has numerous advantages, it suffers from low sensitivity and low detection limits compared to other spectrochemical analytical methods. However, using gold nanoparticles helps to overcome such drawbacks and enhances the LIBS sensitivity in analyzing aluminum

SO2, CS2 and H2S are important decomposition products of insulating gas SF6, and their types and contents are of great significance for the fault diagnosis of SF6 insulated equipment. In this paper, a method of combining ultraviolet absorption spectroscopy and least squares fitting is proposed for the quantitative calculation of SO2, CS2 and H2S mixed gases. All three gases have absorption peaks in

Minimally invasive cancer detection using bio-fluids is been actively pursued due to practical limitations of, though, better suited noninvasive and online in vivo methods. Saliva is one such clinically informative bio-fluid that offers advantage of easy and multiple sample collection. Despite its potential in cancer diagnostics, saliva analysis is challenging due to its heterogeneous composition.

We propose an approach for monitoring the concentration of dissociated carboxylic acid species in dilute aqueous solution. The dissociated acid species are quantified employing inline Raman spectroscopy in combination with Indirect Hard Modeling (IHM) and Multivariate Curve Resolution (MCR). We introduce two different titration-based Hard Model (HM) calibration procedures for a single mono- or polyprotic

Laser-induced carbon plasma in air undergoes various physicochemical processes that affect the kinetic chemistry of species of the plasma plume. We report the time- and space- resolved characterization of carbon plasma produced by infrared nanosecond laser into air at atmospheric pressure. Investigating the laser fluence effect highlights dissociation for fluences > 40 J cm-2, and recombination processes

Previously, we demonstrated that the intensities of cross peaks in a two-dimensional asynchronous spectrum could be enhanced via a change of the sequence of the corresponding 1D spectra. This unusual approach becomes useful when the determination of the sequential order of physicochemical events is not essential. However, we have not known whether the level of noise in the 2D asynchronous spectrum

This study presents the first results of a new type of hyperspectral imager in the longwave thermal radiation range from 8.0-14.0 µm which is simpler than readily available Fourier transform infrared spectroscopy (FTIR) based imagers. Conventional thermography images the thermal radiation from hot objects, but an accurate determination of temperature is hampered by the often unknown emissivities of

In this article a new data treatment based on time resolved photoluminescence are presented. It works as a Streak Camera for infrared. A Time resolved photoluminescence spectrum for the HgCd0.33Te0.67 sample at 120 K was performed and analyzed. Typical time resolved photoluminescence measurements, to compare our results with literature were conducted. An interpretation of the behavior for three different

Heroin is one of the most frequently seized drugs in the South-Eastern Europe. Due to the position in the Balkan route, the Republic of Serbia keeps important role in suppression of the trafficking of heroin for domestic and foreign illegal market. This research is aimed to provide a good scientific approach in the field of seized heroin analysis. Two different forms of heroin are present in the illegal

Fourier transform (FT) spectroscopy is a versatile technique for studying the infrared (IR) optical response of solid-, liquid-, and gas-phase samples. In standard Fourier transform infrared (FT-IR) spectrometers, a light beam passing through a Michelson interferometer is focused onto a sample with condenser optics. This design enables us to examine relatively small samples, but the large solid angle

Characteristics of five subpopulation leukocytes in single-cell levels based on partial principal component analysis coupled with Raman spectroscopy were proposed to recognize the biochemical features of five subpopulation leukocytes. Using wavelet transform, the reconstructed spectra of the low-frequency wavelet coefficients were used to perform multiple principal component analysis based on segmented

The desire for portable Raman spectrometers is continuously driving the development of novel spectrometer architectures where miniaturisation can be achieved without the penalty of a poorer detection performance. Spatial heterodyne spectrometers are emerging as potential candidates for challenging the dominance of traditional grating spectrometers, thanks to their larger etendue and greater potential

The present study has investigated the transformation of sesame oil kept at low temperature during a definite period of time for refinement (called winterization) as an inactive drug ingredient by using two-dimensional difference spectra (2D-DS) analysis of spectra collected by a near-infrared (NIR) and mid-infrared (MIR) dual-wavelength spectrometer (NIR/MIR-DWS). The NIR and MIR spectra were measured

The low accessibility of natural gas fields and transporting pipelines requires portable online analyzers of the composition of natural gas, ensuring nearly chromatographic precision and capable of in situ analysis of a wide range of gases, including infrared-inactive ones (hydrogen, oxygen, nitrogen, chlorine). We have developed an express method of gas analysis meeting all the requirements for analysis

The formation of crystalline zinc soaps (zinc salts of fatty acids) in oil paint layers is a common sign of paint degradation. In this study, we have used infrared spectroscopy to systematically identify differences in structure and composition of crystalline zinc soap phases, and report data analysis methods for structure attribution in challenging oil paint samples. Supported by reported crystal

Analysis of nitrate ester explosives (e.g., nitroglycerine) using gas chromatography–vacuum ultraviolet spectroscopy (GC–VUV) results in their thermal decomposition into nitric oxide, water, carbon monoxide, oxygen, and formaldehyde. These decomposition products exhibit highly structured spectra in the VUV that is not seen in larger molecules. Computational analysis using time-dependent density functional

In this work, principal component analysis (PCA) was utilized to analyze laser-induced breakdown spectroscopy (LIBS) signals of the extracted chicken fat, lamb fat, beef fat, and lard froze using two different freezing methods. The frozen samples were ablated using a neodymium-doped yttrium aluminum garnet (Nd:YAG) laser with a wavelength of 1064 nm, 170 mJ pulse energy, and 6 ns pulse duration to

The cucurbit[n]uril (CB[n]) family of macrocycles are known to bind a variety of small molecules with high affinity. These motifs thus have promise in an ever-growing list of trace detection methods. Surface-enhanced Raman scattering (SERS) detection schemes employing CB[n] motifs exhibit increased sensitivity due to selective concentration of the analyte at the nanoparticle surface, coupled with the

Fractal and polarization analysis of diffusively scattered light is applied to determine the complex relationship between fractal dimension of structural morphology and concentration of chemically active ingredients in two pharmaceutical mixture systems including a series of binary mixtures of acetaminophen in lactose and three multicomponent blends with a proprietary active ingredient. A robust approach

A critical step in Raman spectroscopy is baseline correction. This procedure eliminates the background signals generated by residual Rayleigh scattering or fluorescence. Baseline correction procedures relying on asymmetric loss functions have been employed recently. They operate with a reduced penalty on positive spectral deviations that essentially push down the baseline estimates from invading Raman

Presented here is a novel automated method for determining the trace element composition of bulk thorium by inductively coupled plasma–optical emission spectroscopy (ICP-OES). ICP-OES is a universal approach for measuring the trace elemental impurities present in actinide-rich materials; however, due to the emission rich spectrum of the actinide, a separation from the trace elements is warranted for

Oxidation reactions of alcohols have been of interest due to their broad applications in different fields. Oxoammonium cation (TEMPO+) of 2, 2, 6, 6-tetramethyl piperidine-1-oxyl (TEMPO) is a high-potential oxidant for the selective oxidation of primary alcohols, with hydroxylamine (TEMPOH) as a side product. TEMPO or TEMPO+ has been widely applied for various reactions. However, the conversion mechanisms

Chronic kidney disease (CKD) affects more than 10% of population around the world and is associated with significant morbidity and mortality. In most cases, this disease is developed silently, and it can progress to the end stage renal failure, therefore, early diagnosis becomes critical for initiating effective interventions. Routine diagnosis of CKD requires both blood tests and urinalyses in a clinical

The exposure of mining workers to crystalline particles, e.g., alpha quartz in respirable dust is a ubiquitous global problem in occupational safety and health at surface and underground operations. The challenge of rapid in-field monitoring for direct assessment and adoption of intervention has not been solved satisfactorily to date, as conventional analytical methods such as X-ray diffraction (XRD)

Baseline drift occurs in various measured spectra, and the existence of a baseline signal will influence qualitative and quantitative analyses. Therefore, it is necessary to perform baseline correction or background elimination before spectral analysis. In this paper, a multiple constrained asymmetric least squares method based on the penalized least squares principle is proposed for baseline correction

Tip-enhanced Raman spectroscopy (TERS) is a powerful tool for the characterization of surfaces and two-dimensional materials, delivering both topographical and chemical information with nanometer-scale spatial resolution. Atomic force microscopy (AFM)–TERS combines AFM with a Raman spectrometer and is a very versatile technique, capable of working in vacuum, air, and liquid, and on a variety of different

It has previously been demonstrated that the ratio of the degenerate four wave mixing signal from two hot water line groups near 3231 cm–1 can be used for seedless flame temperature measurements. This paper presents an investigation of the impact of saturation effects on the measured signal intensity from each line group, as well as an estimation of the accuracy of the method. The saturation effects

The impact of altering laser focusing conditions on laser-induced breakdown spectroscopy experiments is investigated under ambient Earth laboratory and simulated Martian atmospheres. Experiments were performed in which the focal spot size was varied on a sample by altering the lens to sample distance with respect to targets of interest. Samples investigated include aluminum, copper, and steel. Specific

Microplastics (MP) are ubiquitous within the environment, but the approaches to analysis of this contaminant are currently quite diverse, with a number of analytical methods available. The comparability of results is hindered as even for a single analytical method such as Fourier transform infrared spectroscopy (FT-IR) the different instruments currently available do not allow a harmonized analysis

Microplastics are of major concerns for society and is currently in the focus of legislators and administrations. A small number of measures to reduce or remove primary sources of microplastics to the environment are currently coming into effect. At the moment, they have not yet tackled important topics such as food safety. However, recent developments such as the 2018 bill in California are requesting

Microplastic research is a rapidly developing field, with urgent needs for high throughput and automated analysis techniques. We conducted a review covering image analysis from optical microscopy, scanning electron microscopy, fluorescence microscopy, and spectral analysis from Fourier transform infrared (FT-IR) spectroscopy, Raman spectroscopy, pyrolysis gas–chromatography mass–spectrometry, and energy

Raman spectra of mineralized tooth tissues were used to build a principal component regression (PCR) age determination model for forensic application. A sample of 71 teeth was obtained from donors aging from 11 to 76 years. No particular selection criteria were applied; teeth affected with various pathological processes were deliberately included to simulate a realistic forensic scenario. In order

A monolithic spatial heterodyne Raman spectrometer (mSHRS) is described, where the optical components of the spectrometer are bonded to make a small, stable, one-piece structure. This builds on previous work, where we described bench top spatial heterodyne Raman spectrometers (SHRS), developed for planetary spacecraft and rovers. The SHRS is based on a fixed grating spatial heterodyne spectrometer

A nondispersive infrared gas analyzer was demonstrated for investigating metal alkylamide precursor delivery for microelectronics vapor deposition processes. The nondispersive infrared analyzer was designed to simultaneously measure the partial pressure of pentakis(dimethylamido) tantalum, a metal precursor employed in high volume manufacturing vapor deposition processes to deposit tantalum nitride

Tip-enhanced Raman spectroscopy (TERS) provides the sensitivity required to obtain the vibrational fingerprint of few molecules. While single molecule detection has been demonstrated in UHV experiments, the sensitivity of the technique in ambient, liquid and electrochemical conditions is still limited. In this work, we present a new strategy to increase the signal-to-noise in TERS by spatial light

A new hyperspectral Raman imaging technique is described using a spatial heterodyne Raman spectrometer (SHRS) and a microlens array (MLA). The new technique enables the simultaneous acquisition of Raman spectra over a wide spectral range at spatially isolated locations within two spatial dimensions (x, y) using a single exposure on a charge-coupled device (CCD) or other detector types such as a complementary

Recent studies to quantify the health risks that fine particulate matter with an aerodynamic less than 2.5 µm (PM2.5) pose use in vitro approaches. One of these approaches is to incubate PM2.5 in artificial lysosomal fluid for a given period at body temperature. These body fluids used have a high ionic strength and as such can be challenging samples to analyze with atomic spectroscopy techniques. As

Mosquito-borne diseases are responsible for considerable morbidity and mortality globally. Given the absence of effective vaccines for most arthropod-borne viruses, mosquito control efforts remain the dominant method of disease prevention. Ideal control efforts begin with entomologic surveillance in order to determine the abundance, identity, and infection status of pathogen-vectoring mosquito populations

Raman spectroscopy is a unique tool for fast analysis of multicomponent gas media. In this work, we studied the features of application of this method for monitoring the syngas (mixture of CO + H2 + CH4 + CO2 + N2) composition. To determine concentrations, we used contour fit method, where the Raman spectrum of mixture is compared with a synthetically calculated spectrum. The effects of pressure changes