Using confocal Raman imaging and other advanced measurement techniques, we study the localized strain characteristics of tungsten diselenide (WSe2), an important nanomaterial used for optoelectronic device applications.
Webinar Date/Time: Wed, Nov 20, 2024 2:00 PM EST
This new terahertz method provides a theoretical reference for studying the relationship between biomolecules and water.
In this study, in situ Raman spectroscopy was used to detect the formation, growth, and evolution of corrosion inside a salt fog chamber. These results pave the way for monitoring the real-time observation of corrosion on metal surfaces.
In recent years, advances in X-ray optics and detectors have enabled the commercialization of laboratory μXRF spectrometers with spot sizes of ~3 to 30 μm that are suitable for routine imaging of element localization, which was previously only available with scanning electron microscopy (SEM-EDS). This new technique opens a variety of new μXRF applications in the food and agricultural sciences, which have the potential to provide researchers with valuable data that can enhance food safety, improve product consistency, and refine our understanding of the mechanisms of elemental uptake and homeostasis in agricultural crops. This month’s column takes a more detailed look at some of those application areas.
IR absorption spectroscopy technology can solve the problem of line aliasing in gas detection. Here, continuous wavelet transform was used in time-frequency analysis to improve spectral component identification and quantitative detection of gases.
In celebration of Spectroscopy’s 35th Anniversary, leading spectroscopists discuss important issues and challenges in analytical spectroscopy.
We examine the feasibility of FT-NIR for the detection of early fungal infections in citrus.
With this cooling system, which maintains the chemical composition and temperature of the frozen sample, a higher S/N was achieved for LIBS analysis of a NaCl solution.
Seaweed has become a popular ingredient in Western diets. Concerns for heavy metals and inorganic arsenic have been raised as potential risks to consumers. Methods for analysis are described, including microwave digestion, HPLC, and ICP-MS for quantitation and speciation.
Of the 78 million tons of plastic packaging manufactured every year, approximately one-third ends up in the ocean, the air, and most foods and beverages. To monitor the proliferation of these plastics, an ultrasonic capture method is demonstrated that produces a 1500-fold enhancement of Raman signals of microplastics in water.
Long chain fatty acids (LCFAs) function as a source of metabolic energy, substrates for membrane biogenesis, and storage of metabolic energy. Oxylipins, oxygenated derivatives of LCFAs, regulate the activity of many cellular processes. Existing methods for the analysis of LCFAs and oxylipins have limited compound coverage and sensitivity that, therefore, prevent their application in biological studies. In this work, we developed a high-throughput LC–MS method for analysis of 51 LCFAs and oxylipins. LCFAs and oxylipins were first extracted from biological samples via solid-phase extraction. The extracted molecules were analyzed by targeted comparative metabolomics. Saturated and monounsaturated LCFAs were analyzed in single ion reaction mode, while polyunsaturated LCFAs and oxylipins were analyzed in multiple reaction monitoring mode. Using this method, we successfully quantified 31 LCFAs and oxylipins from mouse livers.
A novel approach to NIR spectral sensing, using a miniaturized fully-integrated multipixel array of resonant-cavity-enhanced InGaAs photodetectors, enables sensors with a millimeter-scale footprint and wafer-scale fabrication. This multipixel sensor does not measure the full spectrum, but rather a limited number of spectral regions with limited resolution (50–100 nm).
A novel approach to NIR spectral sensing, using a miniaturized fully-integrated multipixel array of resonant-cavity-enhanced InGaAs photodetectors, enables sensors with a millimeter-scale footprint and wafer-scale fabrication. This multipixel sensor does not measure the full spectrum, but rather a limited number of spectral regions with limited resolution (50–100 nm).
The relationship between leaf nitrogen content (LNC) and hyperspectral remote sensing imagery (HYP) was determined to construct an estimation model of the LNC of drip-irrigated sugar beets, to enable real-time monitoring of sugar beet growth and nitrogen management in arid areas.
Tunable diode laser absorption spectroscopy (TDLAS) is combined with an extreme learning machine (ELM) model, tailored by genetic algorithm (GA) parameter searching, to produce a more robust analytical method for trace gas analysis of ethylene.
Per- and poly-fluoroalkyl substances (PFAS) are a family of potentially thousands of synthetic compounds that have long been used in the manufacture of a variety of common products with stain-repellent and nonstick properties. Their signature strong fluorine and carbon bonds make them difficult to break down and, as a result, they are among the most persistent of today’s environmental pollutants. Alarmingly, PFAS can be found in drinking water and have been shown to accumulate in the body with the potential to cause multiple health problems, such as hormone disruption and cancer. Advances in mass spectrometry have facilitated the detection of known PFAS contaminants as well as the identification of poorly studied and novel compounds in watersheds. This article explores the detection of known and novel PFAS contaminants in aqueous film-forming foams and raw drinking water sources in North Carolina, using new advances in mass spectrometry and data acquisition to improve identification and quantitation.
In this article, tunable diode laser absorption spectroscopy (TDLAS) is used to measure ammonia leakage, where a new denoising method combining empirical mode decomposition with the Savitzky-Golay smoothing algorithm (EMD-SG) is proposed to improve the signal-to-noise ratio (SNR) of absorbance signals.
Portable NIR spectroscopy, combined with discrimination analysis (PLS-DA), can be used to rapidly and accurately identify five very similar wood species of the Cinnamomum genus.
Analysis of the compositional variation in living cells is essential for understanding biological processes. Single-cell elemental analysis by triple-quadrupole ICP-MS is emerging as a selective, highly sensitive, and potentially high-throughput technique for the study of constitutive elements, and uptake of metallodrugs (or metal-containing nanomaterials) in single cells.
Detecting metal elements in liquid samples cannot be done efficiently by only using LIBS, but when the technique is combined with appropriate membrane materials, rapid analysis of solution samples can be realized.
Determining the printing sequences of crossed writings and seal stamps is often difficult because the most common methods used are expensive, time-consuming, and cumbersome. A new method using Raman spectral area scanning offers a better alternative while conducting pigment analysis and determining intersection sequences of writings and seal stamps. We explain why.
In this interview, originally published in European Spectroscopy News 44 in 1982, Dave Briggs sat down with 1981 Nobel Prize winner Kai Manne Börje Siegbahn to discuss his career and work in spectroscopy.
This study aimed to establish a fast, accurate method for quality evaluation of herbal medicine using NIR and chemometrics with ultraviolet-visible spectrophotometry (UV-vis) as a standard method to determine the total flavonoids content.
Evaluation of the UV-vis spectra of the reaction product of ytterbium (III) with hematoxylin (HE) indicates the formation of a rare earth complex that further reacts with marine mammal DNA, indicating the potential that this complex may have anti-tumor properties.
Because of their corrosive properties, corrosive lipids are challenging to analyze by ATR-FT-IR. Repeated and prolonged analysis can damage many ATR crystals. Diamond ATR is a better choice for such applications than other ATR crystal materials like ZnSe and Ge. This application note examines a corrosive liquid as it becomes progressively more concentrated using diamond ATR.
This study uses Fourier transform infrared (FT-IR) spectroscopy to analyze how the globular protein ovalbumin's secondary structures transition under varying pH conditions in the presence of the cosolvent xylitol, highlighting the role of noncovalent interactions in these conformational changes.
Utilizing a low-altitude unmanned aerial vehicle (UAV), a hyperspectral remote-sensing system can identify key grass species indicating grassland degradation, developing an ASI index and classification rules and leveraging spectral differences and plant senescence reflectance to effectively monitor and evaluate grassland conditions and degradation.