Hyperspectral imaging (HSI) has emerged as a powerful non-invasive tool for material identification in cultural heritage, integrating imaging and spectroscopy to acquire spatially and spectrally resolved data. This review critically examines the capabilities and limitations of HSI either as a standalone method or in combination with other analytical techniques for identifying materials such as pigments, inks, and dyes in artworks and historical documents. It explores the fundamentals of HSI and recent advances in data analysis, including multivariate analysis, spectral matching, machine learning, and spectral unmixing. Despite these advances, the widespread implementation of this technique in cultural heritage institutions remains limited due to its cost, data complexity, and lack of standardized spectral databases. Future directions include the development of generalized, interpretable identification algorithms and multi-technique data fusion. This review provides conservation scientists and researchers in the field with valuable insights into the realistic potential of HSI for reliable material identification.

Urine provides a noninvasive window into the renal and lymphatic systems, providing molecules (potential markers) from around the body that are detectable using mid-range Fourier transform infrared spectroscopy (MR-FTIR). The benefit of MR-FTIR for urine analysis is the simultaneous sampling of many of the 3000+ urine constituents. The highly condensed spectral information in a single drop of urine potentially provides simpler, faster, and cheaper tests for multiple pathologies in a single test, providing hope for simultaneous testing of different pathologies. The shortage of pathologists in the UK and medical experts worldwide motivates research to improve medical diagnostic technologies, increasing interest in techniques like MR-FTIR urine analysis. Clinical MR-FTIR urine analysis is ideally positioned for review, niche enough for an exhaustive progress report, whilst developed enough to highlight challenges and suitable comparison to current approaches. Before clinical spectroscopy can help patients, clinical validation must be demonstrated. The review highlights milestones toward this goal, like replicated or blinded studies. A section is then dedicated to the experimental considerations already investigated, providing a resource for future FTIR urine analysis study design. The paper concludes by testing a critical variable for transmission MR-FTIR spectroscopy, identified by assessment of reviewed references, discussed in only one, urea hydrogen bonding with H2O, emphasizing the importance of robust dehydration protocols for urine MR-FTIR analysis. Academic and industrial collaborators separately duplicated the experiments, increasing confidence in the analysis repeatability and corresponding clinical value of the findings.

This study assessed the effectiveness of functional near-infrared spectroscopy (fNIRS) in evaluating post-stroke depression after a six-month multi-intervention program. Ninety-two stroke survivors were randomly assigned to either an experimental group (receiving Motivational Interviewing (MI) and Home Rehabilitation) or a control group (Standard Care). Oxyhemoglobin (HbO2) levels in the prefrontal cortex were measured using a 48-channel fNIRS system during a cognitive task at baseline, three months, and six months. Depression was assessed using the Patient Health Questionnaire-9 (PHQ-9). Data were analyzed using the General Linear Model (GLM) and Receiver Operating Characteristic (ROC) curve analysis. The experimental group showed significant improvements in depressive symptoms, along with corresponding changes in HbO2 levels in the left orbitofrontal cortex (OFC). The optimal HbO2 cutoff for predicting depression was −0.47 mmol·mm in the left OFC for the experimental group, −0.07 mmol·mm in the ventrolateral prefrontal cortex (VPC), and 0.29 mmol·mm in the frontopolar prefrontal cortex (FPC) for the control group.

Combustion remains the primary process for energy supply in nowadays society. With the emerging of low-carbon fuels alongside traditional fossil fuels, the increased complexity of thermal-chemical conversion processes call for more accurate diagnostic tools. Compared to traditional offline measurement techniques which are often insufficient in providing precise information, advanced laser diagnostics techniques are increasingly important for providing in-situ measurements in combustion processes due to their high sensitivity, selectivity, and non-intrusive features. In this paper, the developments and applications of laser diagnostics techniques based on the Laser Photofragmentation and Fragment Detection (PF-FD) strategy in combustion are reviewed. First, the motivation for this paper is briefly discussed, as well as the advantages of PF-FD techniques in combustion diagnostics. Second, the recent PF-FD techniques applied in combustion diagnostics are summarized, including Photofragmentation and Prompt Emission (PF-PE), Photofragmentation and Laser Induced Fluorescence (PF-LIF), and Photofragmentation and Laser Absorption Spectroscopy (PF-LAS). The primary focus is on the measurements of species concentrations, velocity/temperature fields, and flame structure using PF-FD, involving hydrocarbons, H2O2/HO2/H2O, ozone, nitrogenous compounds, and alkali metal/heavy metal compounds. Finally, a comparison and outlook of different PF-FD methods in combustion diagnostics, both in the laboratory and the field, are presented.

Recently, a new gas chromatography-vacuum ultraviolet (GC-VUV) detector was created and used for the identification of petroleum and petrochemicals. Information from GC-VUV includes both quantitative and qualitative data. The VUV detector demonstrates exceptional adaptability, sensitivity, and complementary properties in diverse research fields, including environmental, food, and petrochemical research. It achieves low picogram level detection limits and comparable sensitivity to a quadruple MS operated in scan mode, making VUV spectroscopy a competitive and cutting-edge technique. This review aims to shed light on the benefits and quirks of the GC-VUV coupling, which received high acceptance since the advent of a commercial VUV detector. It is aimed in this review to present and discuss the potential applications of GC-VUV technique with respect to the recent development and progress, practical considerations, and industrial implementation in refineries and research laboratories as well as its restrictions.

This study focuses on the application of vibrational spectroscopy—Raman and FT-IR—for detecting microplastics (MPs) in various water bodies, including oceans, lakes, and drinking water. Given the growing concern about the environmental and health impacts of MPs, accurate identification and analysis are essential. The review discusses the fundamental principles of Raman and FT-IR spectroscopy, emphasizing their nondestructive nature and capability to provide detailed chemical identification. Sample preparation methods are explored to enhance detection efficiency, particularly in complex matrices where organic matter may cause spectral interference. Highlighting recent studies, this review aims to evaluate the effectiveness of these techniques in identifying MPs in diverse aquatic systems, and offers insight into the challenges and future perspectives for advancing microplastic research in aquatic environments.

The review reports on investigations and studies that have contributed in the last 20 years (2003–2023) to the clarification of the mechanisms governing the chemical vapor generation (CVG) of hydrides and other volatile metallic species using aqueous phase derivatization with tetrahydridoborate (1-)(THB) and amine boranes, which is widely used in determination and speciation analysis of trace elements by atomic optical and mass spectrometry. The discussion begins with the early investigations leading to definition of the mechanism of hydrolysis of aqueous THB and that of reaction conditions. The new knowledge represents important achievements for the clarification of controversial aspects that plagued CVG for more than 35 years and stimulated further studies which are discussed in detail. They concern with the mechanism of hydrolysis of amine boranes, the mechanism of interferences, the role played by chemical additives and the definition of more general reaction models for CVG, which are valid for both analytical and non-analytical reaction conditions. The latest developments and the analytical applications of the new knowledge to trace element analysis are discussed.

Due to rapid economic development and urbanization, water pollution has posed a significant threat to public health and social stability. Therefore, accurate and rapid monitoring of water quality becomes particularly important and significant. As an environmentally friendly, nondestructive and efficient detection technology, spectral analysis technology provides an effective tool for qualitative analysis and quantitative detection of pollutants in water environment. In this paper, the principle of UV-Vis spectroscopy and near-infrared (NIR) spectroscopy and their application in water quality detection are studied. UV-Vis and NIR spectroscopy techniques for the detection of many kinds of water quality parameters are discussed according to the classification of chemical oxygen demand, organic matter, microbial pollutants, heavy metals and emerging pollutants. The information of light source in spectroscopy measurement and the algorithms used in spectral data processing are summarized. Finally, the application tendency of spectrum technology in water pollution detection is prospected.

Thallium (Tl) pollution have attracted widespread attention in recent years due to is its high toxicity as well as its increasing release into the environment by human activities. Furthermore, its bioaccumulation can lead to various diseases and even death. Hence, accurate determination of Tl in biological and environmental samples is of utmost importance. This review provides an overview of analytical methods for the determination of Tl, drawing from over 200 references published mainly between 2012 and 2022. The reported methods for Tl detection include atomic emission spectrometry, atomic absorption spectrometry, inductively coupled plasma mass spectrometry, and molecular spectroscopy. For detection of Tl in environmental and biological samples, the current trends of sample pretreatment techniques were summarized. Additionally, the speciation analysis of two wo Tl species (i.e., Tl+ and Tl3+) was also briefly discussed.

In this review, we attempt to provide a brief account of laser-induced breakdown spectroscopy (LIBS) methodology and technological developments. We also summarize various methods adopted for exploiting LIBS. Besides, a brief overview of combination of LIBS in conjunction with other methods is also given.