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[Display omitted] •Explorations of LIBS and FTIR-ATR techniques in soil forensic identification.•Optimizations of LIBS and FTIR-ATR in soil forensic identification.•Fusions of the LIBS and FTIR-ATR spectra data in soil forensic analysis.•Applications of LIBS and FTIR-ATR in real cases of soil forensics analysis. Soils are crucial trace evidence that can establish or exclude the relationship between a suspect, victim, or an object at a particular scene, which could contribute to building a case. Laser-induced breakdown spectroscopy (LIBS) and Fourier transform infrared-attenuated total reflectance (FTIR-ATR) spectroscopy have been demonstrated to be effective techniques for soil characterization owing to its being rapid, non-destructive, and convenient analysis with little sample preparation requirements. Therefore, the principles of LIBS and FTIR-ATR techniques for soil forensic analysis in typical soil samples were investigated and their practical feasibility was tested by applying the techniques to forensic soil samples in two criminal cases. Principal component analysis (PCA) of a typical soil sample indicated that five typical soil types were clearly distinguished by LIBS and FTIR-ATR spectra. Variations in the soil elements (i.e., Si, Mg, Al, Ca, K, O, and N) and functional groups (i.e., OH/NH, CC/CO, SiO, CO32−, AlOH, and NH2) are crucial indicators for soil identification. The casework results demonstrated that both LIBS and FTIR-ATR show great potential for forensic soil analysis in future cases.

Aquatic ecology has been greatly threatened by the discharge of effluents of textile and antibiotic industries into natural waters. Herein, an efficient and easily recycled reduced graphene oxide/zirconium oxide nanocomposite has been synthesized using banana peel extract (abbreviated as rGO–ZrO 2 in this work). The X-ray diffraction (XRD), field emission scanning electronic microscopy (FESEM), high-resolution transmission electron microscopy (HRTEM), Brunauer–Emmett–Teller (BET), UV–visible diffuse reflectance spectroscopy (DRS), X-ray photoelectron spectroscopy (XPS), and Fourier transform infrared (FTIR) spectroscopy were used to analyze the synthesized material. The as-prepared rGO-ZrO 2 nanocomposite was employed as a photocatalyst for the decomposition of rhodamine blue (RhB) and crystal violet (CV) dyes, and ciprofloxacin (CIP) antibiotic by illumination with direct sunlight. The RhB and CV were degraded to maximum extent of around 86 and 90%, respectively, over the rGO–ZrO 2 nanocomposite after exposure to direct sunlight for 120 min. On the other hand, the degradation of CIP was approximately 93.1% over the rGO–ZrO 2 nanocomposite in 240 min under same experimental conditions. Further studies were performed regarding the role of parameters like pH, catalyst dose, and scavengers, in order to understand the superiority of rGO-ZrO 2 nanocomposite in degrading organic pollutants. Moreover, the intermediate products and plausible CIP degradation mechanisms were examined using liquid chromatography-mass spectrometry (LC–MS). Moreover, the catalyst was easily separated from the solution and demonstrated good stability and reusability. The RhB, CV, and CIP removal efficiency were 80%, 83%, and 88%, respectively, after five cycles.

• Leaf reflectance spectroscopy is emerging as an effective tool for assessing plant diversity and function. However, the ability of leaf spectra to detect fine-scale plant evolutionary diversity in complicated biological scenarios is not well understood. • We test if reflectance spectra (400–2400 nm) can distinguish species and detect fine-scale population structure and phylogenetic divergence – estimated from genomic data – in two co-occurring, hybridizing, ecotypically differentiated species of Dryas. We also analyze the correlation among taxonomically diagnostic leaf traits to understand the challenges hybrids pose to classification models based on leaf spectra. • Classification models based on leaf spectra identified two species of Dryas with 99.7% overall accuracy and genetic populations with 98.9% overall accuracy. All regions of the spectrum carried significant phylogenetic signal. Hybrids were classified with an average overall accuracy of 80%, and our morphological analysis revealed weak trait correlations within hybrids compared to parent species. • Reflectance spectra captured genetic variation and accurately distinguished fine-scale population structure and hybrids of morphologically similar, closely related species growing in their home environment. Our findings suggest that fine-scale evolutionary diversity is captured by reflectance spectra and should be considered as spectrally-based biodiversity assessments become more prevalent.

Fabrication of easily recyclable photocatalyst with excellent photocatalytic activity for degradation of organic pollutants in wastewater is highly desirable for practical application. In this study, a novel ternary magnetic photocatalyst BiVO 4 /Fe 3 O 4 /reduced graphene oxide (BiVO 4 /Fe 3 O 4 /rGO) was synthesized via a facile hydrothermal strategy. The BiVO 4 /Fe 3 O 4 with 0.5 wt% of rGO (BiVO 4 /Fe 3 O 4 /0.5% rGO) exhibited superior activity, degrading greater than 99% Rhodamine B (RhB) after 120 min solar light radiation. The surface morphology and chemical composition of BiVO 4 /Fe 3 O 4 /rGO were studied by scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, UV visible diffuse reflectance spectroscopy, Fourier transform infrared spectroscopy, and Raman spectroscopy. The free radicals scavenging experiments demonstrated that hole (h + ) and superoxide radical (O 2 •− ) were the dominant species for RhB degradation over BiVO 4 /Fe 3 O 4 /rGO under solar light. The reusability of this composite catalyst was also investigated after five successive runs under an external magnetic field. The BiVO 4 /Fe 3 O 4 /rGO composite was easily separated, and the recycled catalyst retained high photocatalytic activity. This study demonstrates that catalyst BiVO 4 /Fe 3 O 4 /rGO possessed high dye removal efficiency in water treatment with excellent recyclability from water after use. The current study provides a possibility for more practical and sustainable photocatalytic process.

This paper presents a spectroscopic study of emulsions generated with a laser-assisted device. Fourier transform infrared (FTIR), Raman and UV–Vis–NIR reflectance spectra of emulsions, recorded before and after exposure to laser radiation were used to characterize the effect of laser irradiation. The paper also presents a comparison between the calculated IR spectra and the experimental FTIR spectra of an emulsion’s components. FTIR measurements allowed the identification of absorption bands specific to each of the emulsions’ components. Moreover, it enabled the observation of destabilization of the emulsion in real-time. Raman spectroscopy allowed the observation of the modifications at a molecular level, by identifying the vibrations of the representative functional groups and the polymerization of sodium tetradecyl sulfate (STS) molecules by analyzing the evolution of the carbonyl band. UV–Vis–NIR reflectance spectra of emulsions before and after exposure to laser radiation showed that the physical characteristics of the emulsions changed during irradiation—the dimensions of the droplets decreased, leading to an emulsion with a better time stability. These results proved that the employed spectroscopy techniques were powerful tools in emulsion analysis.

This work introduces innovative Bi 2 O 3 -ZnO/TiO 2 (BZT) composite photocatalysts, developed via a simple electrospinning technique. The incorporation of Zn 2+ and Bi 3+ ions was confirmed through high-resolution transmission electron microscopy and X-ray photoelectron spectroscopy (XPS). XPS analysis confirmed the presence of Zn and Bi elements on the surface of TiO 2 nanofibers, with oxidation states of + II and + III, respectively. The band gaps, estimated through the Kubelka–Munk function and ultraviolet-visible diffuse reflectance spectroscopy, decreased from 3.18 eV for pristine TiO 2 to 2.9 eV for the 1%Bi 2 O 3 -ZnO/TiO 2 (1BZT) composites, resulting in improved light-harvesting capabilities. Photocatalytic performance studies, particularly methylene blue degradation under visible light, revealed notable improvements for Bi 2 O 3 -ZnO/TiO 2 systems compared to ZnO/TiO 2 and TiO 2 . The 1%Bi 2 O 3 -ZnO/TiO 2 heterostructure was found as efficient photocatalyst with 98% photodegradation of MB. The maximum rate constant, 0.0234 min − 1 , was observed for 1BZT nanofibers, which was 4.97 and 16.7 times greater than those of ZnO/TiO 2 and TiO 2 , respectively. This enhancement highlights the synergistic effect between Zn 2+ and Bi 3+ , alongside the enhanced visible light absorption by Bi 3+ , which collectively elevated the photocatalytic efficiency. The heterojunction formed among Bi 3+ , Zn 2+ , and Ti 4+ significantly facilitated the separation of photogenerated charge carriers, which is essential for high photocatalytic efficiency. Quenching experiments confirmed the important roles in the photocatalytic degradation of MB were played by • OH and • O −   2 rather than the h + radical under sun light. The 1%Bi 2 O 3 -ZnO/TiO 2 photocatalyst exhibited the highest level of activity and excellent reusability, retaining its photocatalytic performance over multiple cycles. Graphical abstract

Dendritic mesoporous silica nanospheres (DMSNs) possess excellent specific surface areas, pore volumes, and extremely accessible internal spaces. DMSNs have experienced high-speed development in the aspects of synthesis techniques, functionalization strategies, and application fields. It is proved that DMSNs own inherent structural superiorities as catalysts, adsorbents, or reaction platforms. Naturally, researchers are enlightened to conceive and attempt to synthesize dendritic mesoporous titania nanospheres (DMTNs) by replacing Si in DMSNs with Ti, in view of the superior activity and catalytic performance from TiO 2 . Nevertheless, the hydrolysis and condensation rates of the titanium precursors are too fast to develop ideal dendritic textures. To get the goal in a roundabout way, hybrid dendritic mesoporous silica&titania nanospheres (DMSTNs) come into sight. In this work, a series of DMSTNs have been synthesized by the one-pot co-condensation method. For the first time, their morphologies and architectures have been controlled by adjusting the ratio of titanium to silica, stirring speed, reaction temperature, co-solvent, etc. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) have been utilized to directly reveal their differences. The basic physicochemical properties of DMSTNs with fine topological structures have been compared, covering Fourier Transform Infrared spectroscopy (FT-IR), X-ray diffraction (XRD), N 2 adsorption–desorption isotherms, Raman spectrum, X-ray photoelectron spectroscopy (XPS), ultraviolet–visible diffuse reflectance spectroscopy (UV-Vis-DRS), photoluminescence (PL) spectra, etc. Most importantly, these typical DMSTNs can photo-catalytically produce more hydrogen (2.4 ~ 3.6 times) within 1% Pt than that of bare DMSNs under simulated sunlight, owing to Ti in their skeletons. Graphical Abstract

Halide perovskites and their low-dimensional analogs are promising semiconductor materials for solar cells, LEDs, lasers, detectors and other applications in the area of photonics. The most informative optical property of semiconductor photonics materials is the absorption spectrum enabling observation of the fundamental absorption edge, exciton structure, defect-related bands, etc. Traditionally, in the study of halide perovskites, this spectrum is obtained by absorption spectroscopy of thin films or diffuse reflectance spectroscopy of powders. The first method is applicable only to compounds with the developed thin film deposition technology, and in the second case, a large absorption coefficient narrows the observations down to the sample transparency region. In this paper, we suggest the diffuse reflectance spectroscopy with dilution as a method for obtaining the full-range absorption spectrum from halide perovskite powders, and demonstrate its application to practically important cases.

In this study, Boron Nitride Quantum Dots (BNQDs) are successfully synthesized via the hydrothermal method. Additionally, the hydrothermal method is employed to synthesize BNQDs decorated TiO 2 nanograss (BNQDs/TiO 2 NG) from BNQDs decorated TiO 2 (BNQDs/TiO 2 ). To validate the synthesis of different BNQDs samples, fluorescence spectroscopy (FL) is performed, revealing a strong quantum confinement effect resulting from variations in the precursor ratio. The bandgap energies of TiO 2 , BNQDs/TiO 2 , and BNQDs/TiO 2 NG are determined using UV–Vis diffuse reflectance spectroscopy (UV-DRS), demonstrating a reduction in the band gap. A smaller band gap corresponds to a higher thermal conductivity, as there is a negative correlation between thermal conductivity and band gap energy. The study suggests that BNQDs/TiO 2 NG exhibit higher thermal conductivity compared to TiO 2 and BNQDs/TiO 2 . X-ray photoelectron spectroscopy (XPS) reveals the elemental composition of both BNQDs and TiO 2 , including Ti–O, B–N and B–O bonds. High Resolution Transmission Electron Microscopy (HR-TEM) is utilized to examine the morphological attributes of BNQDs/TiO 2 NG. The crystalline structure of the synthesized composites is ascertained using X-ray diffraction (XRD). The photocatalytic degradation of methylene blue (MB) by TiO 2 , BNQDs/TiO 2 , and BNQDs/TiO 2 NG under visible light is also compared. Based on the results, BNQDs/TiO 2 NG is determined to be an effective material for treating wastewater containing organic dyes.

The sol–gel process was applied to prepare ZnO-saponite nanocomposite for environmental remediation and investigation of photocatalysis mechanisms. The nanocomposite followed the photodegradation of Rhodamine B (RhB) as a model dye under irradiation with visible light. The materials were characterized by X-ray diffraction, scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), diffuse reflectance spectroscopy, photoluminescence, Point of zero charges (Pcz), and Brunauer–Emmett–Teller (BET). Reuse, the effect of scavengers, and toxicity were also investigated. The results showed an effective incorporation of the semiconductor on the surface of the support, forming a hexagonal structure with the wurtzite phase of ZnO. The evaluation of texture and morphology showed the effective distribution of ZnO nanoparticles on the surface of the synthesized photocatalyst. The intensified adsorption/photocatalysis process using saponite-based nanocomposite achieved more than 85% RhB dye removal efficiency after 270 min. It followed presented pseudo-first-order kinetics with a constant equal to 6.627 × 10–1 min−1. Furthermore, the evaluation of the effect of scavengers indicated that alcohol played an important role in scavenging hydroxyl radicals. It was stable after evaluating the catalyst after successive cycles, maintaining its structure, as FTIR proved. Furthermore, the studied nanocomposites did not show evidence of toxicity, thus being promising candidates for application in the removal of polluting dye.