Reliable quantitative FT-IR measurements require that the pathlength be known to within 1%. Pathlength estimations based on nominal spacer thickness are not reliable and require that the actual pathlength be measured for accurate data. We demonstrate how.
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.
Analysis of 66 pesticides and 5 mycotoxins regulated by the State of California in cannabis tinctures were analyzed using LC–MS/MS with an ESI source, and LC–MS/MS with an APCI source. A simple, fast, and cheap acetonitrile solvent extraction method was used for sample preparation for good recovery and high throughput, and internal standards were used to compensate for ion suppression effects from the hydrophobic matrix.
Great interest has recently aroused in the study of the dysregulation of chemical elements within tissues. Information about the distribution of elements in biological tissues can contribute to a more complete medical diagnosis, and can guide therapeutic procedures for many pathologies.
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.
This article discusses how FT-IR and SERS is being used to detect counterfeit pharmaceutical drugs.
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.
To study the optical properties of mixed crude oil, the optical constants of samples consisting of two crude oils mixed in different proportions were obtained by the double-thickness transmittance method based on transmittance spectra.
Surface-enhanced Raman spectroscopy (SERS), using gold nanoparticles, is useful for detection of low-levels of many analytes, including the water pollutant malachite green (MG).
Supported by the PSI method, Raman spectroscopy has the capability to analyze the surface structure of nanomaterials, such as graphene, transition metal dichalcogenides (TMD), semiconductors, nanomaterials, and so on.
Depletion of modern mineral resources due to continuous exploitation and utilization makes it economically necessary to quickly identify the locate sources of low-grade ore. Here, we propose a vis-NIR remote sensing method to determine copper content in mining areas as well as to measure the environmental impact of surface mining methods.
Gas chromatography–mass spectrometry (GC–MS) with cold electron ionization (EI) is based on interfacing the GC and MS instruments with supersonic molecular beams (SMB) along with electron ionization of vibrationally cold sample compounds in SMB in a fly-through ion source (hence the name cold EI). GC–MS with cold EI improves all the central performance aspects of GC–MS. These aspects include enhanced molecular ions, improved sample identification, an extended range of compounds amenable for analysis, uniform response to all analytes, faster analysis, greater selectivity, and lower detection limits. In GC–MS with cold EI, the GC elution temperatures can be significantly lowered by reducing the column length and increasing the carrier gas flow rate. Furthermore, the injector temperature can be reduced using a high column flow rate, and sample degradation at the cold EI fly-through ion source is eliminated. Thus, a greater range of thermally labile and low volatility compounds can be analyzed. The extension of the range of compounds and applications amenable for analysis is the most important benefit of cold EI that bridges the gap with LC–MS. Several examples of GC–MS with cold EI applications are discussed including cannabinoids analysis, synthetic organic compounds analysis, and lipids in blood analysis for medical diagnostics.
Accurate determination of the elemental composition of nickel-based alloys is essential, given their use in high-performance equipment. This XRF technique enables rapid and nondestructive detection, as an alternative to existing approaches.
A novel intelligent inversion model integrating multiscale fractal analysis, PCA, and machine learning techniques (RF and SVM) was devised to accurately estimate soil organic matter (SOM) using hyperspectral data.
The use of high-resolution LIBS imaging requires the reduction of acquisition time. The authors describe a new developed system that accomplishes this goal and can be used in various applications where elemental composition and elemental distribution analysis is required.
Software tools for ICP-MS and ICP-OES can help analysts to simplify method setup and reduce the potential for errors.
Although not as widespread in terms of units used worldwide as quadrupole-based inductively coupled plasma–mass spectrometry (ICP-MS) equipment, also multicollector ICP-MS (MC-ICP-MS) instrumentation has revolutionized many fields.
The results in this study indicate that NIR spectroscopy is a potentially promising approach for the rapid identification of different harvest times of Cabernet Sauvignon grapes, and the proposed technique is helpful for the prediction of ripened and over-ripened Cabernet Sauvignon grapes during the harvest time.
Raman measurements of chromite minerals demonstrated that chromium content could be accurately determined, supporting a possible application of portable Raman devices on Earth or in space for mineral analysis of asteroids and planets.
Compressed tablet is the most common form of orally administered drug. The United States Pharmacopeia (USP) chapter <905> requires that dosage uniformity of such products containing less than 25 mg or less than 25% active pharmaceutical ingredients (API) by weight must be analyzed for content uniformity, which is based on the assay of each API in a number of individual dosage units.
To ensure the stable operation of fuel plant desulfurization systems, it is critical to maintain the content of thiosulfate within an appropriate range. This new method for thiosulfate determination is highly sensitive and easy to perform.
The Bouguer-Beer-Lambert law has its limitations and it doesn't always properly reflect the physical phenomena at play. This article examines the law's limitations.
Liquid chromatography coupled with high-resolution mass spectrometry (LC–HRMS) is used in combination with a comprehensive data analysis workflow to screen water samples for potentially hazardous transformation products from organic micropollutants to determine the efficacy of different water treatment methods.
Laser ablation laser ionization time-of-flight mass spectrometry (LALI-TOF-MS) can quantify elemental constituents without the need for matrix-matching, making it attractive for metals testing, particularly for additive manufacturing.
We investigate the effect of an applied electric field on the laser-induced titanium plasma for laser induced breakdown spectroscopy (LIBS) for the purpose of assessing electron density with respect to laser energy.
Compressed tablet is the most common form of orally administered drug. The United States Pharmacopeia (USP) chapter <905> requires that dosage uniformity of such products containing less than 25 mg or less than 25% active pharmaceutical ingredients (API) by weight must be analyzed for content uniformity, which is based on the assay of each API in a number of individual dosage units.