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Microplastic (MPL) abundance is a well-elucidated problem in the marine environment but not so much in the terrestrial environment. In order to contribute to this research gap, a field study was performed in the Yadkin-Pee Dee River Basin. Due to their heterogenous nature and difficulty in characterization, a diverse set of pictorial training data from µ-Raman was used to perform transfer learning on 2 CNNs of interest: GoogLeNet (GN) and ResNet-18 (RN). In the first trial, using 10% of the initial training dataset, the CNNs exhibited high levels of accuracy rates, generally above 90%. Irrespective of spectroscopic mode, marginal improvements in accuracy rates were seen, with the best improvements occurring in the Raman-based models (U[GN(FTIR), RN(Raman), GN(FTIR), and RN(Raman)]: 39, 42, 38.5, and 34.5; p-value: 1,.6753,.9719, and.4978). However, for the external trial, pictorial data from Primpke (FTIR) and DongMiller (Raman) was predicted less accurately, with the largest loss occurring across the following sets: U[GN(Raman) and RN(FTIR)], 45.5 and 35; p-value:,.3268 and.5476. However, set RN fared marginally better, and due to the usage of µ-Raman, and its performance in the 10% trial, RN18_ADAM_.0011 was selected as the champion model for the field study data. In the unknown microparticle (MP) trial, generally, the most ID'd polymer type was CA, PET, and PE representing a relative concentration range for a given water source and area (MPL/MP) of 4.17–37.5%, 4.17–8.33%, and 4.17–8.33% for CNN and OpenSpecy (OS). A FEDS algorithm, equipped with natural and synthetic polymer standards and biological material, used to compare the strength of each model determined similar frequency in ascertaining positive MPL results across both models with corroboration between the CNN and OS around 1/3 of the time. Results indicate the models detect MPLs with similar frequency elucidating comparable strength of the CNN as well as a focus on particle type distribution rather than individual identification. Moreover, the largest influential factor in this study appears to be either laundry wastewater effluent or atmospheric deposition, which is stressed as a primary focus of remediating MPLs in similar freshwater environments. Lastly, it appears that these MPL are of primary origin as opposed to secondary in the oceanic and coastal environments. [ABSTRACT FROM AUTHOR]

Abstract Microplastic (MPL) abundance is a well-elucidated problem in the marine environment but not so much in the terrestrial environment. In order to contribute to this research gap, a field study was performed in the Yadkin-Pee Dee River Basin. Due to their heterogenous nature and difficulty in characterization, a diverse set of pictorial training data from µ-Raman was used to perform transfer learning on 2 CNNs of interest: GoogLeNet (GN) and ResNet-18 (RN). In the first trial, using 10% of the initial training dataset, the CNNs exhibited high levels of accuracy rates, generally above 90%. Irrespective of spectroscopic mode, marginal improvements in accuracy rates were seen, with the best improvements occurring in the Raman-based models (U[GN(FTIR), RN(Raman), GN(FTIR), and RN(Raman)]: 39, 42, 38.5, and 34.5; p-value: 1, .6753, .9719, and .4978). However, for the external trial, pictorial data from Primpke (FTIR) and DongMiller (Raman) was predicted less accurately, with the largest loss occurring across the following sets: U[GN(Raman) and RN(FTIR)], 45.5 and 35; p-value:, .3268 and .5476. However, set RN fared marginally better, and due to the usage of µ-Raman, and its performance in the 10% trial, RN18_ADAM_.0011 was selected as the champion model for the field study data. In the unknown microparticle (MP) trial, generally, the most ID’d polymer type was CA, PET, and PE representing a relative concentration range for a given water source and area (MPL/MP) of 4.17–37.5%, 4.17–8.33%, and 4.17–8.33% for CNN and OpenSpecy (OS). A FEDS algorithm, equipped with natural and synthetic polymer standards and biological material, used to compare the strength of each model determined similar frequency in ascertaining positive MPL results across both models with corroboration between the CNN and OS around 1/3 of the time. Results indicate the models detect MPLs with similar frequency elucidating comparable strength of the CNN as well as a focus on particle type distribution rather than individual identification. Moreover, the largest influential factor in this study appears to be either laundry wastewater effluent or atmospheric deposition, which is stressed as a primary focus of remediating MPLs in similar freshwater environments. Lastly, it appears that these MPL are of primary origin as opposed to secondary in the oceanic and coastal environments.

Abstract In recent years, the presence and migration of PAEs in packaging materials and consumer products has become a serious concern. Based on this concern, the aim of our study is to determine the possible migration potential and speed of PAEs in benthic fish stored in vacuum packaging, as well as to monitor the storage time and type as well as polyethylene (PE) polymer detection.As a result of the analysis performed by µ-Raman spectroscopy, 1 microplastic (MP) of 6 µm in size was determined on the 30th day of storage in whiting fish muscle and the polymer type was found to be Polyethylene (PE) (low density polyethylene: LDPE). Depending on the storage time of the packaging used in the vacuum packaging process, it has been determined that its chemical composition is affected by temperature and different types of polymers are formed. 10 types of PAEs were identified in the packaging material and stored flesh fish: DIBP, DBP, DPENP, DHEXP, BBP, DEHP, DCHP, DNOP, DINP and DDP. While the most dominant PAEs in the packaging material were determined as DEHP, the most dominant PAEs in fish meat were recorded as BBP and the lowest as DMP. The findings provide a motivating model for monitoring the presence and migration of PAEs in foods, while filling an important gap in maintaining a safe food chain.

In recent years, the presence and migration of PAEs in packaging materials and consumer products has become a serious concern. Based on this concern, the aim of our study is to determine the possible migration potential and speed of PAEs in benthic fish stored in vacuum packaging, as well as to monitor the storage time and type as well as polyethylene (PE) polymer detection.As a result of the analysis performed by µ-Raman spectroscopy, 1 microplastic (MP) of 6 µm in size was determined on the 30th day of storage in whiting fish muscle and the polymer type was found to be Polyethylene (PE) (low density polyethylene: LDPE). Depending on the storage time of the packaging used in the vacuum packaging process, it has been determined that its chemical composition is affected by temperature and different types of polymers are formed. 10 types of PAEs were identified in the packaging material and stored flesh fish: DIBP, DBP, DPENP, DHEXP, BBP, DEHP, DCHP, DNOP, DINP and DDP. While the most dominant PAEs in the packaging material were determined as DEHP, the most dominant PAEs in fish meat were recorded as BBP and the lowest as DMP. The findings provide a motivating model for monitoring the presence and migration of PAEs in foods, while filling an important gap in maintaining a safe food chain. [ABSTRACT FROM AUTHOR]

Concern about atmospheric microplastic (MP) contamination has increased in recent years. This study assessed the abundance of airborne anthropogenic particles, including MPs, deposited in rainfall in Bahia Blanca, southwest Buenos Aires, Argentina. Rainwater samples were collected monthly from March to December 2021 using an active wet-only collector consisting of a glass funnel and a PVC pipe that is only open during rain events. Results obtained show that all rain samples contained anthropogenic debris. The term “anthropogenic debris” is used to refer to the total number of particles as not all the particles found could be determined as plastic. Among all the samples, an average deposition of 77 ± 29 items (anthropogenic debris) m−2d−1 was found. The highest deposition was observed in November (148 items m−2d−1) while the lowest was found in March (46 items m−2d−1). Anthropogenic debris ranged in size from 0.1 mm to 3.87 mm with the most abundant particles being smaller than 1 mm (77.8%). The dominant form of particles found were fibers (95%), followed by fragments (3.1%). Blue color predominated (37.2%) in the total number of samples, followed by light blue (23.3%) and black (21.7%). Further, small particles (

The widespread use of plastics has revolutionized modern life, but also led to environmental pollution. Although microplastics (MPs) have been detected in various environments, their presence in the atmosphere, particularly in Brazil, is poorly studied. This research investigated atmospheric MP concentrations at Alvaro Guião School in São Carlos, Brazil, from 2021 to 2022. Outdoor MP concentrations ranged from the limit of detection (LOD) to 168.03 items m−2 day−1, and indoor concentrations ranged from LOD to 60.16 items m−2 day−1. Predominantly, these MPs were fragments, even in the indoor environment, suggesting abundant sources, such as resuspension. Seasonal variations were not observed for outdoor fragments and fibers, nor for indoor fragments. However, indoor fiber concentrations were higher during the dry season (p > 0.05), likely due to winter clothing and reduced ventilation. Fragment sizes were mainly <60 μm, while fibers ranged from <60 μm to 3000–5000 μm. Polyester was the primary MP component (83–100% outdoors and 29–100% indoors), followed by ethylene vinyl acetate (EVA, 0–17% outdoors and 0–57% indoors), common in synthetic clothing and school supplies, respectively. Other plastics, found in packaging and bottles, like polyethylene (0–14%) and polyethylene terephthalate (0–6%), were also identified indoors. This study not only enhances the current understanding, but also pioneers analyses within a school environment. Despite being a work in progress, this study has already shown the presence of plastic particles in environments where children, one of the most susceptible groups to air pollution, spend a significant portion of their time. Furthermore, it can assist in developing an assessment of acceptable levels and guidelines. [Display omitted] • Atmospheric microplastic concentrations ranged from LOD to 168.03 items m−2 day−1. • Indoor fiber levels higher in dry season due to winter clothing and reduced ventilation. • School supplies and synthetic clothing were key sources of microplastics in the area. • Polyester and EVA were the most abundant polymers in these school's collected samples. • Polymer composition reflects the site profile: a large school in a high-traffic area. [ABSTRACT FROM AUTHOR]

The emission of microfibers (MFs) into all environmental matrices, including biota, is a global concern, but appropriate methodologies aimed at biomonitoring these pollutants are still in an exploratory stage. In this work a new method is presented for the extraction of airborne anthropogenic microfibers (MFs) from the leaves of Pittosporum tobira. The method is a sequential extraction consisting of tape tearing followed by water floating, ethanol extraction, and wet peroxidation, which considered at first outermost MFs, weakly adhering to leaf surface, and deeper MFs partly embedded in waxy cuticle layer. Tape tearing removed the highest fraction of MFs (about 75%), followed by water washing, ethanol and peroxidation. The constant ratio between the MFs collected in the successive extraction steps indicated that the protocol proposed is reliable and reproducible. Moreover, based on the tape tearing step, MFs number was significantly higher on the upper surface of the leaves, whereas MFs were significantly longer on the lower surface. A "reverse" extraction protocol in which tape tearing followed three water-washings demonstrated that a noticeable fraction of MFs still adhered to the leaf after water floating. SEM observation of the leaf surface highlighted the structural changes occurring during the extraction, with leaf surface becoming clearer and smoother at each step. Raman spectroscopy highlighted the presence of different kind of anthropogenic MFs, with microplastics representing 50%, and polyethylene terephthalate 39% of total MFs. Due to reproducible results and easy handling of the leaves, we encourage the use of P. tobira as a biomonitor of airborne MFs and suggest that a simplified extraction method based on tape tearing alone could be a fast and useful alternative to be adopted in biomonitoring protocols. [Display omitted] • Airborne microfibers were extracted in P. tobira leaf by tape, water, ethanol and H 2 O 2. • Tape tearing extracted 75% MFs followed by water (15%), ethanol and H 2 O 2. • In all leaf samples a constant proportion of MFs was found at each extraction step. • SEM observation highlighted the effects of the extraction on leaf surface architecture. • Raman microspectroscopy identified a 50% of MFs as microplastics, mainly PET. [ABSTRACT FROM AUTHOR]

In recent years, microplastic (MP) pollution has garnered significant attention owing to its ability to permeate various ecosystems, including soil. These particles can infiltrate the environment, either directly or through the degradation of larger plastic items. Despite growing concerns, standardized methods for quantification are still lacking. This study aimed to screen for the presence of MPs in agricultural soils while incorporating green analytical principles in the methodology. A density separation followed by centrifugation was employed, based on the principles of the QuEChERS extraction method. This approach minimized sample quantities, reagent consumption, and waste production, ensuring efficient extraction and analysis. Recovery tests using certified soils spiked with pristine MPs, specifically polystyrene, polypropylene (PP), and ethylene-vinyl acetate for larger MPs (3-5 mm), and low-density polyethylene, polyamide 6, and tire wear particles for smaller MPs (15-300 μm),achieved recovery levels exceeding 69% for smaller MPs and over 91% for larger particles. Spectroscopic analysis revealed slight alterations in the Raman spectra of MPs after extraction. Transitioning to agricultural soil analysis has revealed challenges, including spectral interferences. Nine mesoplastics (plastic items 5-20 mm) were detected, predominantly consisting of PP and PE, along with seven MPs, three of which were individually identified as PE-based, while the remainder were inconclusive, including one fiber. The evaluation of the method's sustainability using the Analytical Eco-Scale and Analytical Greenness Calculator Metric (AGREE), with scores of 82 out of 100 and 0.66 out of 1, demonstrated its potential as a liable approach to MP analysis in soils. This study highlights the potential of integrating green analytical chemistry principles into MP extraction methodologies and emphasizes the value of the proposed QuEChERs-based approach for improving the sustainability and efficiency of MP monitoring in agricultural soils., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. The authors declare the following financial interests/personal relationships which may be considered as potential competing interests:, (Copyright © 2024. Published by Elsevier Ltd.)

Abstract In this study, in order to analyze the materials and techniques used for the production of the inscribed plaques, multi-analytical scientific approach, including optical microscopy (OM), scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM–EDS), X-ray diffraction (XRD), micro-attenuated total reflection Fourier transform infrared spectroscopy (μ-ATR-FTIR), and micro-Raman spectroscopy (μ-Raman), were used to explore the materials and techniques utilized to create the “Chun Rong Xuan Mao” birthday inscribed plaque of the Qing Dynasty. The results showed that the plaque was made of cypress wood and decorative parts consisting of the surface lacquer layers, plaster lacquer layers and primer lacquer layers. Chinese lacquer was the principal material used in the surface lacquer layers; gypsum and Chinese lacquer were the materials used in the plaster lacquer layers; and the primer lacquer layers was composed of Chinese lacquer, calcite, and mixed pigments by cinnabar and minium. The surface lacquer layers of the inscribed plaque were lacquered black. Gypsum lacquer plaster has been commonly used in the ground layer of lacquerware in modern history. This study confirmed the existence of technology to make lacquerware using gypsum lacquer plaster in the Bashu area during the late Qing Dynasty. Moreover, this study not only provides new findings regarding the traditional production of inscribed plaques and offers technical support for the protection and restoration of such plaques but also has great significance to exploring the history of ancient techniques of lacquering and decorating lacquerware.

Green contemporary art conservation cleaning methods are explored as sustainable museum practices, ensuring the conservator's health and reducing the environmental impact. The performance of selected biodegradable cleaning agents, namely deionised (DI) water, a chelate based on trisodium salt of methylglycinediacetic acid (MGDA), Trilon® M, a non-ionic surfactant based on alkoxylated fatty alcohols (Plurafac® LF900), and two solvents, limonene and ethyl lactate, was evaluated for the surface cleaning of polymethyl methacrylate (PMMA), polylactic acid (PLA), polypropylene (PP), and plasticized polyvinyl chloride (pPVC). Plastic mockups were used untreated or artificially soiled, simulating particulate matter or sebum stains produced by handling. Furthermore, the efficacy of ink removal from the plastic's surface was evaluated. Surface examination was carried out using optical microscopy (OM), scanning electron microscopy (SEM), and atomic force microscopy (AFM), while µ-Raman and gloss measurements complemented the cleaning assessment methodology. The cleaning agents' potency depends on the type of plastic, precluding a general cleaning protocol. However, their cleaning efficacy is very promising, enriching the available choices for the cleaning of plastics, using sustainable materials and practices. This study offers valuable information to the conservation field regarding the effects of the selected biodegradable cleaning agents on each type of plastic, their application method, and their cleaning efficacy for the removal of different types of soil and ink. [ABSTRACT FROM AUTHOR]

This work aims to characterise the chemical composition of Roman opaque red glass sectilia dated to the 2nd century A.D and to shed light on Roman glassmaking production of different shades of red, from red to reddish-brown. Due to the lack of technical historical sources for this period many questions about technological aspects still remain. In this project a multi-disciplinary approach is in progress to investigate the red glass sectilia with several red hues from the Imperial Villa of Lucius Verus (161−169 A.D.) in Rome. First, colorimetric measurements were taken to identify the various red hues. The second step was chemical characterization of the samples and the identification of crystalline colouring phases. Particle Induced X-Ray Emission (PIXE) analysis was used to investigate the chemical composition of these glass samples, while the crystalline phases were identified by Raman Spectroscopy and Scanning Electrons Microscope with Energy Dispersive X-ray Spectrometry (SEM-EDS). Using SEM-EDS nanoparticles were detected as a colouring agent, the chemical composition and the morphology of which has been studied in depth. This information has been compared with the colorimetric analysis to establish any correlation with the different colour hues.

In this study, in order to analyze the materials and techniques used for the production of the inscribed plaques, multi-analytical scientific approach, including optical microscopy (OM), scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM–EDS), X-ray diffraction (XRD), micro-attenuated total reflection Fourier transform infrared spectroscopy (μ-ATR-FTIR), and micro-Raman spectroscopy (μ-Raman), were used to explore the materials and techniques utilized to create the "Chun Rong Xuan Mao" birthday inscribed plaque of the Qing Dynasty. The results showed that the plaque was made of cypress wood and decorative parts consisting of the surface lacquer layers, plaster lacquer layers and primer lacquer layers. Chinese lacquer was the principal material used in the surface lacquer layers; gypsum and Chinese lacquer were the materials used in the plaster lacquer layers; and the primer lacquer layers was composed of Chinese lacquer, calcite, and mixed pigments by cinnabar and minium. The surface lacquer layers of the inscribed plaque were lacquered black. Gypsum lacquer plaster has been commonly used in the ground layer of lacquerware in modern history. This study confirmed the existence of technology to make lacquerware using gypsum lacquer plaster in the Bashu area during the late Qing Dynasty. Moreover, this study not only provides new findings regarding the traditional production of inscribed plaques and offers technical support for the protection and restoration of such plaques but also has great significance to exploring the history of ancient techniques of lacquering and decorating lacquerware. [ABSTRACT FROM AUTHOR]

Copyright of Ege Journal of Fisheries & Aquatic Sciences (EgeJFAS) / Su Ürünleri Dergisi is the property of Ege Journal of Fisheries & Aquatic Sciences (EgeJFAS) / Su Urunleri Dergisi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Highlights • Microplastics were found in coastal waters and in fish gastrointestinal tract from the Tyrrhenian Sea. • Microplastics appeared in fragments or in filamentous shapes, in water and in fish respectively. • Microplastics have been characterized by FT-IR and Raman spectroscopies. Abstract In this work it is reported for the first time the characterization of microplastics from sea water samples and in two congener species of seabreams: Pagellus erythrinus and P. bogaraveo, Mediterranean fish species of great commercial importance. An experimental survey was conducted on May–June 2017 in the southernmost part of the Tyrrhenian Sea. Microplastics found in the sea water and in the grastrointestinal tract of two teleosts were characterized by Raman and IR spectroscopies. Microplastics found in sea water samples appeared in the form of fragments made of plastics of low and high density (PVC and LPDE). All the microplastics found in fish belonged to Nylon 66, typical fibers used in industry and in fisheries. Our findings highlighted the importance of further studies along the food web chain for a better understanding of the diffusion and possible consequences of this terrible threat. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • The two K-Ca-Si glass compositions show different alteration behaviour. • Glass structure plays a dominant role in early stages under similar ageing conditions. • The Pb2+ and Ca2+ content may relate with more reactive structural arrangements. • Preservation state of extant pieces agrees with the replica's early stages. Abstract Several K-Ca-Si glass compositions typical of Central-European glassworks are susceptible to damage beyond recall, even in mild museum conservative conditions. In order to provide a comprehensive picture of the deterioration process, replica samples were produced and exposed to four different museum-like environments. The corrosion experiment was followed by the use of ToF-SIMS, μ -Raman and μ -FTIR, performing a systematic compositional and structural study for the early stages (one year) of surface alteration. This work demonstrates the dominant role of Pb2+ and Ca2+ content for the inferable existence of connected conduction pathways, with strong implications on the surface's hydration, alkali-diffusion and hydrolysis. [ABSTRACT FROM AUTHOR]

This work focuses on the study of the 19th century yellow chromate pigments based on barium (BaCrO), zinc (4ZnCrO·KO·3HO) and strontium (SrCrO). These pigments, which are reported to shift in hue and darken, have been found in 19th century artworks. A better understanding of their historic manufacture will contribute to the visual/chemical interpretation of change in these colours. Research was carried out on the Winsor & Newton (W&N) 19th century archive database providing a unique insight into their manufacturing processes. One hundred and three production records were found, 69% for barium, 25% for zinc and 6% for strontium chromates, mainly under the names Lemon, Citron and Strontian Yellow, respectively. Analysis of the records shows that each pigment is characterised by only one synthetic pathway. The low number of records found for the production of strontium chromate suggests W&N was not selling this pigment formulation on a large scale. Furthermore, contrary to what the authors have discovered for W&N chrome yellow pigments, extenders were not added to these pigment formulations, most probably due to their lower tinting strength (TS). The latter was calculated in comparison to pure chrome yellow (PbCrO, 100% TS) resulting in 92% for barium, 65% for zinc potassium and 78% for strontium chromate pigments. This indicates that W&N was probably using extenders primarily to adjust pigment properties and not necessarily as a means to reduce their costs. Pigment reconstructions following the main methods of synthesis were characterised by complementary analytical techniques: Fibre optic reflectance spectroscopy, X-ray diffraction, micro-Raman and micro-Fourier transform infrared spectroscopies. These pigments can be clearly distinguished on the basis of their infrared CrO asymmetric stretching fingerprint profile (between 1000 and 700 cm) and of their Raman CrO stretching bands (850-950 cm). This enabled their identification in historic paint samples: a tube of late 19th century W&N Lemon Yellow oil paint and micro-samples from paintings by three Portuguese painters, António Silva Porto (1850-1893), João Marques de Oliveira (1853-1927) and Amadeo de Souza-Cardoso (1887-1918). The good correlation found between the reconstructions and historic samples validates their use as reference materials for future photochemical studies. [ABSTRACT FROM AUTHOR]

The gelatin-silver halide black and white prints represent an enormous photography heritage with a great value. Unaesthetic phenomena, the foxing stains that are caused by microbial growth on surface, have been described in stamps, drawings, books, and tissues but, until now, scarcely for photographic materials. In this study, a combination of various techniques, including culture-dependent and culture-independent approaches (RNA and DNA analysis), scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS) and μ-Raman spectroscopy supported by X-ray fluorescence analysis (XRF), permitted to describe the microbial contamination dynamics of foxing stains present on the surface of two gelatin-silver halide photographs. The investigation provided also information on the effects of microbial activity on the materials' chemistry of the two prints. The action of microbial community resulted locally in either (a) formation of mixed aluminum-iron-potassium phosphate compounds that could be attributed to the hydrolytic activity of bacteria, (b) leaching of barite, (c) precipitation of a mixture of oxides, and (d) a change in the barium sulfate chemical structures. [ABSTRACT FROM AUTHOR]

Abstract SiGe islands have been proposed for applications in the fields of microelectronics, optoelectronics and thermoelectrics. Although most of the works in literature are based on MBE, one of the possible advantages of low-energy plasma-enhanced chemical vapor deposition (LEPECVD) is a wider range of deposition rates, which in turn results in the possibility of growing islands with a high Ge concentration. We will show that LEPECVD can be effectively used for the controlled growth of ordered arrays of SiGe islands. In order to control the nucleation of the islands, patterned Si (001) substrates were obtained by e-beam lithography (EBL) and dry etching. We realized periodic circular pits with diameters ranging from 80 to 300 nm and depths from 65 to 75 nm. Subsequently, thin films (0.8–3.2 nm) of pure Ge were deposited by LEPECVD, resulting in regular and uniform arrays of Ge-rich islands. LEPECVD allowed the use of a wide range of growth rates (0.01–0.1 nm s−1) and substrates temperatures (600–750°C), so that the Ge content of the islands could be varied. Island morphology was characterized by AFM, while μ-Raman was used to analyze the Ge content inside the islands and the composition differences between islands on patterned and unpatterned areas of the substrate.

Concern about atmospheric microplastic (MP) contamination has increased in recent years. This study assessed the abundance of airborne anthropogenic particles, including MPs, deposited in rainfall in Bahia Blanca, southwest Buenos Aires, Argentina. Rainwater samples were collected monthly from March to December 2021 using an active wet-only collector consisting of a glass funnel and a PVC pipe that is only open during rain events. Results obtained show that all rain samples contained anthropogenic debris. The term "anthropogenic debris" is used to refer to the total number of particles as not all the particles found could be determined as plastic. Among all the samples, an average deposition of 77 ± 29 items (anthropogenic debris) m -2 d -1 was found. The highest deposition was observed in November (148 items m -2 d -1 ) while the lowest was found in March (46 items m -2 d -1 ). Anthropogenic debris ranged in size from 0.1 mm to 3.87 mm with the most abundant particles being smaller than 1 mm (77.8%). The dominant form of particles found were fibers (95%), followed by fragments (3.1%). Blue color predominated (37.2%) in the total number of samples, followed by light blue (23.3%) and black (21.7%). Further, small particles (<2 mm), apparently composed of mineral material and plastic fibers, were recognized. The chemical composition of suspected MPs was examined by Raman microscopy. The analysis of μ-Raman spectra confirmed the presence of polystyrene, polyethylene terephthalate, and polyethylene vinyl acetate fibers and provided evidence of fibers containing industrial additives such as indigo dye. This is the first assessment of MP pollution in rain in Argentina., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 The Authors. Published by Elsevier Ltd.)

In this work, we report the successful formation of MgO doped TiO2 nanocrystals (NCs) by simple wet-chemical method. The XRD exhibits a marginal decrease in the crystalline size of TiO2 nanosamples by the addition of MgO dopant. UV-Vis spectral analysis shows that the addition of MgO in TiO2 resulted in the red shift of the absorption edge. The optical energy band-gap and molecular vibrational analysis of doped nanosample was ascertained from pho-toluminescence (PL) and micro-Raman scattering technique respectively. HR-TEM analysis reveals that the substitution has sharply reduced the particle size of TiO2NCs. [ABSTRACT FROM AUTHOR]

SiGe islands have been proposed for applications in the fields of microelectronics, optoelectronics and thermoelectrics. Although most of the works in literature are based on MBE, one of the possible advantages of low-energy plasma-enhanced chemical vapor deposition (LEPECVD) is a wider range of deposition rates, which in turn results in the possibility of growing islands with a high Ge concentration. We will show that LEPECVD can be effectively used for the controlled growth of ordered arrays of SiGe islands. In order to control the nucleation of the islands, patterned Si (001) substrates were obtained by e-beam lithography (EBL) and dry etching. We realized periodic circular pits with diameters ranging from 80 to 300 nm and depths from 65 to 75 nm. Subsequently, thin films (0.8-3.2 nm) of pure Ge were deposited by LEPECVD, resulting in regular and uniform arrays of Ge-rich islands. LEPECVD allowed the use of a wide range of growth rates (0.01-0.1 nm s) and substrates temperatures (600-750°C), so that the Ge content of the islands could be varied. Island morphology was characterized by AFM, while μ-Raman was used to analyze the Ge content inside the islands and the composition differences between islands on patterned and unpatterned areas of the substrate. [ABSTRACT FROM AUTHOR]

Abstract: High aspect ratio Zinc Oxide (ZnO) nanowires (NWs) were synthesized by template based one-step electrochemical deposition (OSECD) technique. The electro-reduction of hydroxide ions in the presence of Zn2+ ions within Zn(NO3)2 is involved in the growth of ultra thin NWs arrays. Field Emission Scanning Electron Microscopy (FESEM) images revealed that the growth rates of different crystal faces, (0001) and , were different at different deposition potential for the high aspect ratios ZnO NWs arrays. The n-type semiconductor conductivity of ZnO NWs was ascertained by a Hot-Probe approach. X-ray diffraction results demonstrated that the grown ZnO NWs had wurtzite crystal structure with unit cell parameters a =2.93Å, c =5.45Å and a deterioration of preferred (101) orientation is observed at more negative deposition potentials. Small angle X-ray scattering (SAXS) results evidenced that the NW arrays grown at −1.2V have higher fraction of larger crystallites. Micro-Raman spectroscopy analysis showed that the variation in E 2 (high) vibration mode at 435cm−1 is coupled with an increase in electro acceptor oxygen atoms incorporated within ZnO NWs at −1.2V. [Copyright &y& Elsevier]

This work presents strategic multi-analytical investigations performed on "Orange Car Crash" by Andy Warhol in order to make a well-informed conservation decision. For determining the type of binding medium used in the artwork, Pyrolysis–Gas Chromatography/Mass Spectrometry (Py–GC/MS) and Thermally Assisted Hydrolysis and Methylation of GC/MS (THM–GC/MS) were employed. The presence of a coating was investigated by Py–GC/MS. Moreover, the comprehension and elucidation of the paint stratigraphy were studied by examining cross-sections of samples taken from both canvases with Optical Microscopy (OM) under reflected visible (Vis) and ultraviolet light (UV) and by Scanning Electron Microscopy with Energy Dispersive X-ray spectroscopy (SEM–EDX). The investigation of possible synthetic organic pigments (SOPs) and extenders was performed by µ-Raman spectroscopy, while micro-Attenuated Total Reflection of Fourier-Transform Attenuated Total Reflection (µ-ATR–FTIR) allowed us to assign each component detected by Py–GC/MS or THM–GC/MS to a specific layer. The data collected from "Orange Car Crash" show mostly the application of acrylic-based paint as well as alkyd with rosin acids-based ink, thus providing fundamental information about the paint stratigraphy and chemical composition of each layer. In addition to the goal of informing an appropriate conservation–restoration strategy, this work represents a rare scientific study of a work by Andy Warhol. [ABSTRACT FROM AUTHOR]

Various crystallite size estimation methods were used to analyze X-ray diffractograms of spherical cerium dioxide and titanium dioxide anatase nanoparticles aiming to evaluate their reliability and limitations. The microstructural parameters were estimated from several integral breadth methods such as Scherrer, Monshi, Williamson–Hall, and their variants: (i) uniform deformation model, (ii) uniform strain deformation model, and (iii) uniform deformation energy density model. We also employed the size–strain plot and Halder–Wagner method. For this purpose, an instrumental resolution function of an Al2O3 standard was used to subtract the instrumental broadening to estimate the crystallite sizes and strain, and the linear regression analysis was used to compare all the models based on the coefficient of determination. The Rietveld whole powder pattern decomposition method was introduced for comparison purposes, being the best candidate to fit the X-ray diffraction data of metal-oxide nanoparticles. Refined microstructural parameters were obtained using the anisotropic spherical harmonic size approach and correlated with the above estimation methods and transmission electron microscopy images. In addition, μ-Raman spectra were recorded for each material, estimating the mean crystallite size for comparison by means of a phonon confinement model. [ABSTRACT FROM AUTHOR]

This work used a multi-analytical approach to characterize two 19th century ambrotypes and was motivated by the lack of insight on these historical objects. Photographic imaging and optical microscopy (OM) were used to identify abrasions, cracks related to reticulation, tarnishing, and other aspects associated to production and degradation processes. With variable pressure scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (EDS) these processes were seen with great detail and further characterized. Elemental point analysis and elemental mapping showed that the photosensitive material used was silver iodide. Degradation compounds were found as silver and chlorine-containing compounds. In one of the items, the tarnishing area also contained redeposited silver in a ring-shape surrounding a nucleus rich in silver, copper, and sulfur, in addition to copper-based salts. EDS analyses also identified that the supports were common soda-lime-silica glasses, refined with arsenic; and showed that a pigment rich in iron was used in both items to hand color the cheeks, extended with aluminum silicates alone or mixed with barium sulfate. The μ-Raman study pointed out that a synthetic Mars pigment was employed. μ-Fourier-transform infrared spectroscopy analyses identified collodion as the binder. Shellac was used as a protective varnish in one of the items and a gum was possibly employed on the other. Bitumen was used for the background in one ambrotype.