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The production of fiber-reinforced polymer (FRP) composites has predominantly relied on thermoset resins, such as polyester, vinyl ester, and epoxy. This study represents a pioneering effort in assessing the durability of a new thermoplastic resin for pultruded FRP rebars used in concrete applications. Given the emerging environmental and sustainability concerns—notably the increasing demand for recyclability—thermoplastic matrix composites offer distinct advantages. More reliable and cost-effective processing techniques involving in situ polymerization of a new liquid thermoplastic acrylic resin during manufacturing have recently been developed. The newly developed thermoplastic resin has been tailored for use in the pultrusion process. One significant advantage of the novel thermoplastic resin is its liquid reactive nature, which facilitates superior impregnation and fiber–matrix bonding, leading to notable enhancements in end-use properties—particularly durability and long-term performance such as fatigue and creep resistance—even under alkaline conditions. The objective of this study was to assess the durability performance of the newly developed thermoplastic resin compared with the most commonly used resin (vinyl ester) for pultrusion of FRP bars. Laboratory accelerated aging testing was conducted under water, saline, and alkaline environments at temperatures of 23°C and 40°C for durations of 1,000 and 3,000 h using dog-bone specimens. The specimens were subsequently analyzed with differential scanning calorimetry, scanning electronic microscopy, Fourier transform infrared spectroscopy, and tensile tests. The results indicated that the physicomechanical and microstructural properties of the newly developed thermoplastic resin were not significantly affected by aging environments, performing similarly to vinyl-ester resin. The tensile strength retention was 95%‒98% after exposure to the various environments. Furthermore, one-way analysis of variance analysis revealed no significant difference in the tensile strength of specimens before and after exposure. The results of this study show the feasibility, efficiency, and long-term durability of the newly developed thermoplastic resin for pultruding FRP-reinforcing bars. [ABSTRACT FROM AUTHOR]

Waste tires, used in combination with polymers, have been extensively employed in the construction of asphalt pavements. The performance of these hybrid asphalts varies depending on the manufacturing process, the characteristics of the neat binder, and other factors. The present study aims to investigate the effect of crumb rubber, polymer, and neat asphalt on physicochemical and rheological properties of terminal blend rubberized asphalt (TBRA). Thermal gravimetric (TG) testing was performed to analyze the component distribution of different crumb rubber modifiers (CRMs). Fourier transform infrared spectroscopy (FTIR), gel permeation chromatography (GPC), and solubility and storage stability tests were used to characterize the physicochemical properties of TBRA binders. The rotational viscosity (RV) test, high-temperature performance grade (PG), and rheological master curve were used to compare the rheological properties of various TBRA binders, respectively. Results indicated that crumb rubber and neat binder characteristics, as well as the addition of polymer, impact TBRA performance. However, the influence of neat binder and polymer is more significant than that of crumb rubber. The primary differences in the physicochemical properties of TBRA prepared with different crumb rubber types are related to solubility and degradation degree. The interaction between Zhonghai neat asphalt and crumb rubber is weaker than that of ESSO and Jinshan asphalt, as evidenced by a comparison of molecular weight distribution. Moreover, 3.0% styrene-butadiene-styrene (SBS) polymer can significantly improves the elastic property of TBRA produced with ESSO neat asphalt, which is evidenced by similar phase angle plateau region with 4.5% SBS modified asphalt. [ABSTRACT FROM AUTHOR]

As a potential long-life pavement material, the high brittleness of epoxy asphalt prevents its application. Recycled from waste tires, crumb rubber (CR) can be used with styrene-butadiene-styrene (SBS) to prepare SBS/CR composite modified asphalt. The main objective of this paper is to conduct the material design of epoxy asphalt with SBS, CR, and core-shell rubber (CSR) to toughen the epoxy asphalt and enhance its performance. First, SBS modified epoxy asphalt and SBS/CR composite modified epoxy asphalt (CMEA) were prepared to optimize the toughening materials based on tensile tests. Subsequently, based on the optimized material, the optimal proportion was determined through the response surface method by the Design-Expert software. Third, the microscopic morphology of different epoxy asphalt was observed by laser scanning confocal microscopy (LSCM), and the changes in functional groups were tracked using Fourier transform infrared spectroscopy to reveal the toughening mechanism. Finally, the viscosity test was carried out on the optimal SBS/CR-CSR CMEA at different temperatures to determine its mixing temperature and allowable time. The results show that the SBS/CR-CSR CMEA is the best toughening method, and the optimal epoxy and CSR proportion is 37% and 12%, respectively. Its tensile strength increases by 467.11% and elongation at break increases by 68.73% compared with unmodified epoxy asphalt. The formation of interpenetrating polymer network structure between the SBS/CR network and epoxy resin network, as well as the change in the benzene ring that determines the softness and toughness, may be the main strengthening and toughening mechanisms. The suitable mixing temperature is 160°C for the optimal SBS/CR-CSR CMEA in this paper, which reduces about 20°C compared with conventional CR or SBS/CR composite modified asphalt, providing better environmental benefits. Overall, the SBS/CR-CSR CMEA presents a new solution for the promotion and application of epoxy asphalt. [ABSTRACT FROM AUTHOR]

Freshwater ecosystems, especially lakes, constitute vital reservoirs of potable water, irrigation resources, and aquaculture habitats. However, there is a lack of comprehensive data regarding the prevalence of microplastics (MPs) in freshwater lakes of densely populated metropolitan regions in the Indian Subcontinent. In this study, we have investigated the qualitative and quantitative attributes of MPs in the surface waters of four important lakes in Pune, India: (i) Kasarsai, (ii) Pashan, (iii) Manas, and (iv) Mastani. Our analyses revealed prevalent contamination across all four lakes, with Kasarsai lake exhibiting the highest mean MPs abundance of 14.03 ± 5.41 particles/L. Primary morphotype of MPs detected in the water samples were fibres and the dominant size was between 100 µm to 1000 µm. Additionally, in terms of colour, transparent microplastics were prominent. Fourier Transform Infrared Spectroscopy (FTIR) revealed that polyethylene (PE), polypropylene (PP), polystyrene (PS), and polyethylene terephthalate (PET) were the main types of MPs present in water samples. Furthermore, we assessed the abundance of MPs ingested by commercially available edible fish Tilapia, Oreochromis niloticus, collected from these lakes. We observed maximum ingestion of MPs in the fish from Kasarsai lake, which was 2.8 ± 2.9 particles per individual fish. To evaluate the possible health risks on humans, Estimated Daily intake (EDI) and Microplastics Cancer Risk (MPCR) index were determined for adults and children. EDI of PP was highest for Kasarsai and Manas lake, while, EDI of PE was predominant for Pashan and Mastani lake. For all four lakes, the MPCR index of PE was highest in both adults and children, with the maximum reaching to 0.52 for children consuming water from Pashan lake. Our findings raise concerns about the potential negative effects of MPs on freshwater ecosystem and the health of humans consuming the water and fish from such lakes. An ambitious strategy involving the collective efforts of the general public is required to address this hazard. [ABSTRACT FROM AUTHOR]

Several thin film deposition techniques for oxide semiconducting materials have been developed. In this study, we employed an innovative technique known as chemical wet and dry (CWD) technique to deposit undoped SnO2 thin films on soda lime glass (SLG) and quartz substrates. This approach is an upgraded variant of the dip-coating process, involving controlled substrate withdrawal and in situ annealing in an inert gas atmosphere, ensuring uniform thickness control and contamination-free coating. The presence of a well-made undoped SnO2 thin film on SLG and quartz substrates was confirmed using grazing incidence x-ray diffraction (GIXRD). The films exhibit a mixed state of crystalline and amorphous nature, characterized by the presence of broad, strong peaks, suggesting Debye–Scherrer broadening. Furthermore, field emission scanning electron microscopy (FE-SEM) examinations showed an even distribution of particles on the film's surface, with particle sizes measuring between 10.58 nm and 9.17 nm. Fourier transform infrared (FT-IR) spectroscopy was utilized to detect functional groups within the film. This determination was substantiated by energy-dispersive x-ray spectroscopy (EDAX) analysis, confirming the film's composition. Optical investigations revealed that the films deposited on both SLG and quartz substrates possess remarkable transparency, exceeding 70% in the visible spectrum. The bandgap values range from 3.05 eV to 3.02 eV for SnO2 thin films deposited on SLG and quartz substrates, respectively. The variations in Hall mobilities, attributed to the impact of grain size, have been recognized, confirming the material's n-type characteristics as confirmed by Hall effect assessments. These prepared samples show promising prospects for use in forthcoming transparent conductive and optoelectronic devices, based on the aforementioned data and discoveries. [ABSTRACT FROM AUTHOR]

Total oil and grease (TOG) in water is measured in industrial process waters to determine the concentration of petroleum products present. A common application for TOG measurement is to detect a hydrocarbon leak in circulated cooling water systems. A hydrocarbon leak from a heat exchanger has a negative effect on the stable operation of upgrading and refinery units. Detecting and quantifying a hydrocarbon leak is straightforward; however, identifying the source of the leak can be very time consuming and require a lot of trial and error. In this study, a solvent‐free TOG method using ClearShot extractors and Fourier transform infrared spectroscopy (FTIR) was developed and optimized for the quantification of bitumen derived hydrocarbon analytes in water. This was further expanded upon to develop a rapid method for hydrocarbon identification in the cooling water by combining chemical fingerprinting with a discriminant analysis classification model. Following the optimized solvent‐free TOG method, chemical fingerprints for six different hydrocarbon classes in water were analyzed by FTIR. The classification model for these hydrocarbon classes was constructed using a discriminant analysis algorithm with a 100% classification rate at a TOG mass loading greater than 150 μg. The optimized solvent‐free TOG method decreases exposure risk and ergonomic strain for technologists, improving overall safety and environmental performance. The hydrocarbon fingerprinting enables rapid prediction of a leak source which reduces the time and analysis required to isolate a leak as well as reducing the cost and environmental impact associated with blowdown and purge (disposal and treatment) of contaminated water. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the sequential hydrolysis of the biomass from unconventional and versatile Y. lipolytica to recover mannoproteins, carbohydrates, and other compounds as well as to determine the antioxidant activity of ultrafiltered fractions. The crude biomass underwent autolysis, and the resulting supernatant fraction was used for mannoprotein recovery via precipitation with ethanol. The precipitate obtained after autolysis underwent acid hydrolysis, and the resulting supernatant was ultrafiltered, precipitated, and characterized. The process yields were 55.5% and 46.14% for the crude biomass grown in glucose and glycerol, respectively. The mannoprotein with higher carbohydrate content (from crude biomass grown in glycerol) exhibited a higher emulsification index of 47.35% and thermal stability (60% weight loss). In contrast, the mannoprotein with higher protein content (from crude biomass grown in glucose) showed a better surface tension reduction of 44.50 mN/m. The technological properties showed that the crude biomass and the food ingredients are feasible to apply in food processing. The fractionation of the acid hydrolysis portion allowed the evaluation of the antioxidant power synergism among the components present in the hydrolysate, mostly the protein peptide chain. The sequential hydrolysis method is viable for extracting valuable products from Y. lipolytica. [ABSTRACT FROM AUTHOR]

In this study, the nanocomposite of eggshell membrane is synthesized with ZnO by the chemical bath deposition (CBD) method, and eggshell membrane, which is used as a template, and decomposed. The end product obtained is nanoflowers of zinc oxide (ZnFs). The petals of nanoflowers obtained are of hexagonal cross-section similar to the unit cell structure of zinc oxide. The CBD parameters of temperature, reaction time, and solution pH were varied extensively during this study to obtain optimized parameters for the growth of ZnFs. The obtained nanoflower structure was analyzed using various characterization techniques of Scanning Electron Microscopy (SEM), Energy Dispersive X-Ray Spectroscopy (EDX), X-Ray Diffraction (XRD), and Fourier Transform Infrared Spectroscopy (FTIR). [ABSTRACT FROM AUTHOR]

The processing of Petroleum-based oil has contributed to environmental challenges such as climate change. Recently, research attention has been shifted to oil extraction from different non-edible seeds as a suitable substitute. Accordingly, this study examines the physiochemical characterization, and the effect of extraction temperature on the yield of waste Citrus sinensis seed [orange seed (OS)] bio oil. Studies on the prevalent functional group, fatty acid methyl ester compositions and thermal oxidative stability were carried out using the Fourier transform infrared spectroscopy (FTIR), gas chromatography-mass spectroscopy (GCMS) and differential scanning calorimetry (DSC), respectively. The oil content of the OS bio oil was 46.26%w/w. The high iodine number (31.47 mg/100 g) and low pour point (4.50 °C) of the OS bio oil showed its high content of unsaturated fatty acid. The FTIR functional group of the OS bio oil showed predominantly alkane of CH stretching, aldehydes, esters, and carboxylic acid. The chemical composition of the OS bio oil as determined by GCMS (massHunter/library/NIST 14.1) showed the occurrence of octadecadienoic and oleic acids as poly-saturated and saturated fat found in plant glycosides and vegetable fats and oil. The DSC thermal stability analysis showed the possible existence of mixed triglycerides. Finally, the result from the physiochemical characterization compositions, and functional group the OS bio oil indicated its potential as a suitable substitute for petroleum-based oil.

The products of intertidal and super tidal (splash zone) corrosion on steel piles have been characterised at 3 UK sites with contrasting environmental conditions in order to determine corrosion reaction mechanism and if a common mechanism for accelerated low water corrosion occurs across sites. Intertidal corrosion samples at Shoreham and Newhaven ports show an internal composition of iron mono- and bi-sulphide, with intermediate sulphur oxidation state compounds, and an outer surface dominated by iron oxides and oxyhydroxides with a component of iron sulphates. The FTIR spectra are characteristic of sulphate green rust. In contrast, samples from Southend have all sulphur species below detection levels and are dominated by iron oxides and oxyhydroxides. Carbon binding energy spectra are consistent with the development of biofilms at all sites except for a splash zone sample at Southend. The results demonstrate a common mechanism for ALWC at Newhaven and Shoreham, involving the action of sulphate-reducing bacteria generating iron sulphides on the steel surface. These are subsequently oxidised to produce sulphate green rust, which may in turn oxidise to produce lepidocrocite. At Southend differences in environment are inferred to restrict the activity of sulphate reducing bacteria, resulting in direct oxidation of steel to generate iron oxyhydroxide gels, which subsequently recrystallise, dehydrate and oxidise to goethite, magnetite and ultimately hematite in both splash zone and intertidal samples. The multi-technique approach used here characterises the full range of corrosion products.

Applying foamed warm-mix asphalt (FWA) containing recycled asphalt pavement (RAP) binder in pavement construction technology is an energy-saving and resource-recycling approach. However, the effectiveness of blended binders in improving road performance depends on the storage stability and compatibility in the binder's composition to be effective and durable. To address the compatibility and storage stability issues of the foamed warm reclaimed asphalt (FWRA) in the actual practice, 15 FWRA samples were designed considering varying RAP binder contents and storage conditions. The conventional binder index properties, rheological property, storage stability, and compatible performances were fully characterized. Fourier transform infrared spectroscopy (FTIR) analysis was conducted to understand the internal chemical reactions and corresponding mechanisms, and bivariate correlation analysis was employed to evaluate the relationship between independent variables. The testing results showed that the proposed testing configurations were validated to simulate the storage condition in the actual practice. Increased RAP binder content can worsen the compatibility of unstored FWRA, but relatively satisfactory compatibility can be obtained when the RAP binder content is relatively low. Regardless of the content of RAP binder, the blended FWRA binder is less compatible after the final storage stability test, and thus appropriate modification methods should be proposed to improve the compatibility after storage in the future. FTIR results showed the macromolecular asphaltenes of RAP binder migrate downward during the storage stability test, leading to poor compatibility of FWRA. The B of FTIR is suggested as the microscopic evaluation index, and G*/sinδ difference (35°C) is suggested as the macroscopic performance verification index of storage stability for FWRA. [ABSTRACT FROM AUTHOR]

A biodegradable polymer, the poly(butylene adipate co‐terephthalate) (PBAT), was compounded with the microcrystalline cellulose (MCC) obtained from different sources (such as wheat stalk and rice husk powder) to prepare the polymer composites. The two components, here found to be compatible, as evidenced by the Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM). Further assessment of the compounded fibers with the organic solvent, the toluene, illustrated the nature of the wetting phenomena of MCC by PBAT. The SEM observation showed the wrapping of the PBAT layer onto the MCC phase after the removal of the polymer matrix. The FTIR spectrum showed the presence of the PBAT carbonyl peak on extracted fibers from the composite via solvent removal. It could be concluded that the PBAT could wet the MCC effectively in the composites suggesting the potential of enhancing their properties. Highlights: A biodegradable polymer, the PBAT, melt‐mixed with plant‐based natural fiber.The fiber in composites was found to be wetted with the PBAT layer.H‐bonding between the CO group of PBAT and the OH group of fiber caused wetting.Raw, processed, and silane‐treated fibers showed similar wetting phenomena. [ABSTRACT FROM AUTHOR]

This study investigates the aging mechanisms and effects of outdoor natural exposure aging (NEA) on bitumen in the Tibetan Autonomous Region of China. Unmodified bitumen (No. 90) and styrene–butadiene–styrene (SBS)-modified bitumen were exposed to natural weathering for 0, 4, and 8 months, and their aged samples were collected and analyzed. Dynamic shear rheology (DSR) and Fourier transform infrared spectroscopy (FTIR) were employed to examine the changes in rheological properties and chemical composition of the samples during NEA. The study also assessed the aging extent of bitumen using the complex modulus aging index (CMI), phase angle aging index (PAI), and rutting factor growth rate. FTIR was utilized to quantitatively evaluate the variations in functional group indices with NEA time. The correlation analysis between the conventional binder properties and functional group indices facilitated a deeper understanding of the aging behavior. The results revealed the differences in temperature sensitivity and aging resistance between unmodified bitumen (No. 90) and SBS-modified bitumen under NEA. This research offers insights into bitumen aging in high-altitude regions and emphasizes the intrinsic role of chemical functional group changes in inducing macroscopic indicator changes during NEA. [ABSTRACT FROM AUTHOR]

IntroductionThe Screaming Mummy of Cairo Egyptian-Museum Store, is an anonymous woman with a wide-open mouth coded as CIT8, discovered beneath Theban Tomb 71 (TT71) which is the burial site of Senmut’s relatives, the architect of 18th-Dynasty Queen Hatschepsut (1479–1458 BC). The study aims to evaluate if combining computed tomography (CT) with scientific investigations and archeological data of the Screaming Mummy CIT8 will reveal information about its physical appearance, health, cause of death, and mummification.MethodsWe CT-scanned the mummy and created reconstructed images. Scanning-Electron-Microscope (SEM), Fourier-Transform-Infrared-Spectroscopy (FTIR), and X-ray-Diffraction-Analysis (XRD) were used to investigate mummy skin, hair, and wig samples. We compared our findings to previous data.ResultsComputed tomography estimated the age of death to be 48.1 years ±14.6 based on the pubic symphyseal surface. CT detected mild-to-moderate teeth attrition, and joints degeneration. The desiccated brain and viscera remained in situ. FTIR revealed the wig is formed of midrib date palm that shows in CT as spiral low density fibers. The wig fibers are partially coated with a thick substance that is inspected as black consolidation and identified as crystalline by XRD, comparable to material found in an ancient wig-making workshop. FTIR showed that the skin, hair, and wig samples were treated with imported juniper resin had anti-bacterial and insecticidal properties. The skin and wig samples contained frankincense, and the hair sample contained henna.DiscussionCombining the advantages of paleoradiology to the scientific investigations, provided enhanced comprehension of the mummy CIT8 and ancient Egyptian wig structure and material. CT scanning non-invasively showed the mummy’s inner and exterior morphology, and estimated the age of death as 48 years. CT evaluated the mummification technique based on retained viscera and absence of embalming packs. The scientific tests revealed expensive imported embalming materials, contradicting the traditional belief that the non-removal of the viscera implied poor mummification, resulting in careless embalmers sealing the mouth. The widely opened mouth could be a result of facial expression of suffering before death, fixed by cadaveric spasm. The study also explores how rigor mortis, tissue decomposition, burial techniques, and postmortem alterations may contribute to a mummy’s screaming appearance.

2,2,6,6-tetramethylpiperidine-N-oxyl (TEMPO) and its derivatives are well-established catalysts for various oxidation processes, despite its hazardous nature, causing harm to aquatic ecosystems. Thus, the reuse of TEMPO with a sustained high activity has gained significant importance for its industrial application, which has led to the development of supported TEMPO catalyst. In this context, the efficiency of the support process acquires high relevance. Therefore, this research is aimed at the improvement of the TEMPO supported on silica magnetically modified with Fe3O4 through the application of an online Fourier transform infrared spectroscopy (FTIR) probe to monitor its synthesis. FTIR effectively controlled the synthesis of supported TEMPO, by tracking online the concentration of 3-aminopropyltriethoxysilane (APTES) and tetraethyl orthosilicate (TEOS). Additionally, the presence of Fe3O4 particles in the core of the catalyst allowed its convenient recovery and subsequent reuse. Furthermore, the supported TEMPO catalyst was successfully applied in the oxidation of cellulose to produce nano/microfibrils. The carboxyl groups of the initial untreated cellulose increase from 0.05 mmol/g to 0.68 mmol/g with the supported TEMPO catalyst in presence of sodium hypochlorite and sodium bromide at 50 °C.

Taking Jinggang pomelo peel essential oil (JPPEO) as the research object, two methods of steam distillation and low-temperature continuous phase transition were used for extraction. Orthogonal test was used to study the effects of extraction temperature, extraction pressure and extraction time on the yield of essential oil of Jinggang pomelo peel. At the same time, the physicochemical properties and chemical composition of essential oil were analysed. The results showed that the optimum extraction process of essential oil extracted by low-temperature continuous phase transition （L-JPPEO）was obtained as follows: particle size 30 mesh, extraction temperature 55 ℃, extraction pressure 0.6 MPa, extraction time 60 min, and the analysis temperature 70 ℃. At this time, the extraction rate was 10.99‰, the yield of L-JPPEO was 2.88 times higher than that extracted by steam distillation (H-JPPEO). The physicochemical properties of the essential oil of JPPEO extracted by low-temperature continuous phase transition showed that the content of unsaturated fat acid was higher, the content of free fatty acid was lower, the content of esters was lower. FTIR identified L-JPPEO and H-JPPEO containing terpenes, alcohols, phenols, aldehydes and carbonyl compounds. GC-MS technology identified 23 and 32 compounds from H-JPPEO and L-JPPEO samples, respectively. Among which 15 compounds were detected in both essential oils, the relative content of D-limonene was the highest, the relative content in L-JPPEO was 4.75±0.16 μg/mL, while the relative content in H-JPPEO was 640.93±44.47 μg/mL. HS-GC-IMS identified 71 compounds from both extraction methods of essential oils. Compared with steam distillation, low-temperature continuous phase change extraction technology extracted more terpenes (45.75%), ketones (7.68%), esters (15.85%), and acids (5.62%).

Objective Fourier transform infrared spectroscopy （FTIR） was used to analyze myocardial infarction tissues at different stages of pathological change to achieve the forensic pathology diagnosis of acute and old myocardial infarction. Methods FTIR spectra data of early ischemic myocardium, necrotic myocardium, and myocardial fibrous tissue in the left ventricular anterior wall of the sudden death group of atherosclerotic heart disease and the myocardium of the normal control group were collected using hematoxylin-eosin （HE） and immunohistochemistry （IHC） staining as a reference, and the data were analyzed using multivariate statistical analysis. Results The mean normalized spectra of control myocardium, early ischemic myocardium and necrotic myocardium were relatively similar, but the mean second derivative spectra were significantly different. The peak intensity of secondary structure of proteins in early ischemic myocardium was significantly higher than in other types of myocardium, and the peak intensity of the α-helix in necrotic myocardium was the lowest. The peaks of amide Ⅰ and amide Ⅱ in the mean normalized spectra of myocardial fibrous tissue significantly shifted towards higher wave numbers, the peak intensities of amide Ⅱ and amide Ⅲ were higher than those of other types of myocardium, and the peak intensities at 1 338, 1 284, 1 238 and 1 204 cm-1 in the mean second derivative spectra were significantly enhanced. Principal component analysis （PCA） and partial least square-discriminant analysis （PLS-DA） showed that FTIR could distinguish different types of myocardium. Conclusion FTIR technique has the potential to diagnose acute and old myocardial infarction, and provides a new basis for the analysis of the causes of sudden cardiac death.

The duration and maximum combustion temperature of vegetation fires are important fire properties with implications for ecology, hydrology, hazard potential, and many other processes. Directly measuring maximum combustion temperature during vegetation fires is difficult. However, chemical transformations associated with temperature are reflected in the chemical properties of charcoals (a by-product of fire). Therefore, charcoal could be used indirectly to determine the maximum combustion temperature of vegetation fires with application to palaeoecological charcoal records. To evaluate the reliability of charcoal chemistry as an indicator of maximum combustion temperature, we studied the chemical properties of charcoal formed through two laboratory methods at measured temperatures. Using a muffle furnace, we generated charcoal from the woody material of ten different tree and shrub species at seven distinct peak temperatures (from 200°C to 800°C in 100°C increments). Additionally, we simulated more natural combustion conditions by burning woody material and leaves of four tree species in a combustion facility instrumented with thermocouples, including thermocouples inside and outside of tree branches. Charcoal samples generated in these controlled settings were analyzed using Fourier Transform Infrared (FTIR) spectroscopy to characterize their chemical properties. The Modern Analogue Technique (MAT) was employed on FTIR spectra of muffle furnace charcoal to assess the accuracy of inferring maximum pyrolysis temperature. The MAT model temperature matching accuracy improved from 46% for all analogues to 81% when including ±100°C. Furthermore, we used MAT to compare charcoal created in the combustion facility with muffle furnace charcoal. Our findings indicate that the spectra of charcoals generated in a combustion facility can be accurately matched with muffle furnace-created charcoals of similar temperatures using MAT, and the accuracy improved when comparing the maximum pyrolysis temperature from muffle furnace charcoal with the maximum inner temperature of the combustion facility charcoal. This suggests that charcoal produced in a muffle furnace may be representative of the inner maximum temperatures for vegetation fire-produced charcoals. [ABSTRACT FROM AUTHOR]

Passivation material is a key material for repairing heavy metal contaminated soil in farmland. To study and develop efficient soil heavy metal passivator, thiol-modified montmorillonite was studied. Montmorillonite was used as the raw material, and the thiol group was loaded on the surface or interlayer of montmorillonite to prepare thiol-modified montmorillonite. The characteristics of thiol-modified montmorillonite were characterized by XRD, SEM, TEM and FTIR, and the indoor soil culture test was carried out. The thiol-modified montmorillonite not only added C-H and S-H covalent bonds, but also enhanced the activity of -OH and C=O chemical bonds, and could adsorb with Cd2+ by thiol and hydroxyl coordination. As a result, the occurrence form of Cd in the soil was significantly changed, the ion exchange state was greatly reduced, and the available Cd in the soil absorbed by the crop roots was significantly reduced. After adding 1%, 3% and 5% thiol-modified montmorillonite, the available Cd in soil decreased by 21.92%, 69.11% and 82.90%, respectively. The passivation effect of montmorillonite on soil Cd was significantly improved after thiol modification, and the decrease of available Cd in soil tended to increase with the increase of thiol-modified montmorillonite. [ABSTRACT FROM AUTHOR]

To investigate the trend of functional groups of matrix asphalt, styrene butadiene styrene ( SBS) modifiers, and their modified asphalt with aging time, and to analyze their aging modes. Using Fourier transform infrared spectroscopy (FTIR) and bending beam rheometer (BBR) tests, low-temperature performance tests were conducted on two types of asphalt binders aged for 0, 1, 5, 8, 24, 48, 72 h. Functional group analysis was conducted with SBS modifier to establish the relationship between the functional groups of the two asphalt binders and their low-temperature performance. The results show that SBS modifier aging are contributed by polybutadiene and polystyrene, the SBS modifier aging mode is degraded mainly alkene and alkane in the thermal oxidation process. Two kinds of asphalt binders aging mode are volatilized light oil and reacted with oxygen to form a cross-linked. The trend of SBS modifier at the characteristic peaks in infrared absorption spectra is different and independent of its modified asphalt. Two kinds of asphalt binders carbonyl index is correlative with creep compliance derivative, and low-temperature deformation capacity of asphalt binder is reflected by carbonyl index. [ABSTRACT FROM AUTHOR]

In this work, we extracted chitosan from marine amphipods associated with aquaculture facilities and tested its use in crop protection. The obtained chitosan was 2.5 ± 0.3% of initial ground amphipod dry weight. The chemical nature of chitosan from amphipod extracts was confirmed via Raman scattering spectroscopy and Fourier transform infrared spectroscopy (FTIR). This chitosan showed an 85.7–84.3% deacetylation degree. Chitosan from biofouling amphipods at 1 mg·mL−1 virtually arrested conidia germination (ca. sixfold reduction from controls) of the banana wilt pathogenic fungus Fusarium oxysporum f. sp cubense Tropical Race 4 (FocTR4). This concentration reduced (ca. twofold) the conidia germination of the biocontrol fungus Pochonia chlamydosporia (Pc123). Chitosan from amphipods at low concentrations (0.01 mg·mL−1) still reduced FocTR4 germination but did not affect Pc123. This is the first time that chitosan is obtained from biofouling amphipods. This new chitosan valorizes aquaculture residues and has potential for biomanaging the diseases of food security crops such as bananas. [ABSTRACT FROM AUTHOR]

Pharmaceutical manufacturing is reliant upon bioprocessing approaches to generate the range of therapeutic products that are available today. The high cost of production, susceptibility to process failure, and requirement to achieve consistent, high-quality product means that process monitoring is paramount during manufacturing. Process analytic technologies (PAT) are key to ensuring high quality product is produced at all stages of development. Spectroscopy-based technologies are well suited as PAT approaches as they are non-destructive and require minimum sample preparation. This study explored the use of a novel attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy platform, which utilises disposable internal reflection elements (IREs), as a method of upstream bioprocess monitoring. The platform was used to characterise organism health and to quantify cellular metabolites in growth media using quantification models to predict glucose and lactic acid levels both singularly and combined. Separation of the healthy and nutrient deficient cells within PC space was clearly apparent, indicating this technique could be used to characterise these classes. For the metabolite quantification, the binary models yielded R2 values of 0.969 for glucose, 0.976 for lactic acid. When quantifying the metabolites in tandem using a multi-output partial least squares model, the corresponding R2 value was 0.980. This initial study highlights the suitability of the platform for bioprocess monitoring and paves the way for future in-line developments.

The duration and maximum combustion temperature of vegetation fires are important fire properties with implications for ecology, hydrology, hazard potential, and many other processes. Directly measuring maximum combustion temperature during vegetation fires is difficult. However, chemical transformations associated with temperature are reflected in the chemical properties of charcoals (a by-product of fire). Therefore, charcoal could be used indirectly to determine the maximum combustion temperature of vegetation fires with application to palaeoecological charcoal records. To evaluate the reliability of charcoal chemistry as an indicator of maximum combustion temperature, we studied the chemical properties of charcoal formed through two laboratory methods at measured temperatures. Using a muffle furnace, we generated charcoal from the woody material of ten different tree and shrub species at seven distinct peak temperatures (from 200°C to 800°C in 100°C increments). Additionally, we simulated more natural combustion conditions by burning woody material and leaves of four tree species in a combustion facility instrumented with thermocouples, including thermocouples inside and outside of tree branches. Charcoal samples generated in these controlled settings were analyzed using Fourier Transform Infrared (FTIR) spectroscopy to characterize their chemical properties. The Modern Analogue Technique (MAT) was employed on FTIR spectra of muffle furnace charcoal to assess the accuracy of inferring maximum pyrolysis temperature. The MAT model temperature matching accuracy improved from 46% for all analogues to 81% when including ±100°C. Furthermore, we used MAT to compare charcoal created in the combustion facility with muffle furnace charcoal. Our findings indicate that the spectra of charcoals generated in a combustion facility can be accurately matched with muffle furnace-created charcoals of similar temperatures using MAT, and the accuracy improved when comparing the maximum pyrolysis temperature from muffle furnace charcoal with the maximum inner temperature of the combustion facility charcoal. This suggests that charcoal produced in a muffle furnace may be representative of the inner maximum temperatures for vegetation fire-produced charcoals.

Reduced glutathione, or L-glutathione, is a tripeptide protein that occurs naturally in almost all cells of the human body. It is an antioxidant and plays a significant role in neutralizing oxidative stress. Oxidative stress is responsible for promoting many diseases and abnormalities in the body. This antioxidant decreases with time, and resulting in a number of disorders. To overcome these issues, experts recommend taking glutathione supplements. This study was aimed to design glutathione-loaded polyvinyl alcohol nanofibers, considering the properties of nanofibers that could be used as glutathione supplements to improve the deficiency of glutathione in the human body. With the electrospinning technique, poly (vinyl alcohol) loaded glutathione nanofibers were designed. The prepared nanofibers were characterized using Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR), X-ray diffraction (XRD), and Ultraviolet-Visible Spectroscopy (UV–Vis) techniques. The antioxidant activity of the nanofibers was also determined; the activity indicated the eradication of free radicals.

This experimental research investigates the influence of geopolymerization factors such as Na2O dosages, water and mineral admixture [bentonite (BT), burnt lime (BL), and ground granulated blast furnace slag (GGBS)] on physiomechanical properties of the pelletized fly ash (FA)–based aggregates. Taguchi's L9 orthogonal array was adopted to design the mixing ratios for three kinds of fly ash–based aggregates (in the combinations of FA-BT, FA-BL, and FA-GGBS). The degree of geopolymerization of the produced aggregates was characterized using thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), and a scanning electron microscope (SEM). Most influential response indices in the production of pelletized aggregates were identified using gray relational analysis. The physiomechanical characteristics of the fly-ash aggregates were significantly improved by admixing BL than that of GGBS and BT. However, pelletization efficiency was seen to be superior for GGBS-substituted fly-ash aggregates. The quantified amount of hydration products, i.e., sodium alumino-silicate hydrate (N-A-S-H)/calcium alumino-silicate hydrate (C-A-S-H) for fly ash–based aggregates intensified on increasing Na2O and mineral admixture dosages. The results strongly suggest the existence of a linear relationship between the quantified amount of N-A-S-H/C-A-S-H and individual pellet strength of produced aggregate. The FTIR spectrum showed strong and broadened bands of Si-O terminal for all types of aggregates, representing the conversion of unreacted minerals to chains of aluminosilicate gel (geopolymerized hydration product). Further, it can also be inferred from gray relational analysis that among all other factors, Na2O content significantly impacted the engineering properties of produced fly ash–based aggregates. [ABSTRACT FROM AUTHOR]

In this work, we have analyzed key characteristics of nickel oxide (NiO) thin films using combined experimental and computational approaches for smart window applications. Thermo Gravimetric Analysis (TGA) depicts that nickel oxide films are stable beyond 275 °C.The XRD pattern revealed the single phase of the materials. FTIR studies confirm the stretching vibrational band of Ni−O. The current‐voltage analysis shows the semiconducting behavior of the materials. The synthesized NiO thin films have shown prominent electrochromic response with a wide linear range, better cyclic stability, high durability, and fast response time. The sample having concentration of 0.05 M/25 mL has best semi‐conductive response as rapid increase in current occurs above 0.8 V. Moreover, the electrochemical and optical properties have shown reversible redox behavior of the synthesized NiO thin films with changing their appearance from original greenish gray to the dark brown in the selected potential range. In addition, the computational study has also been performed for deep study of electronic charge conduction mechanism and photo response of NiO thin layer using Tran‐Blaha modified Becke Johnson (TB‐mBJ) approach. These fabricated NiO thin films have been utilized as an active electrode for electro chromic devices in smart window applications. [ABSTRACT FROM AUTHOR]

Axial DC magnetic field–assisted multi-capillary underwater air bubble discharge plasma jet has been used to study the productions of reactive oxygen species. Analyses of optical emission data revealed that the rotational (Tr) and vibrational temperatures (Tv) of plasma species slightly increased with magnetic field strength. The electron temperature (Te) and density (ne) increased almost linearly with magnetic field strength. Te increased from 0.53 to 0.59 eV, whereas ne increased from 1.03 × 1015 cm−3 to 1.33 × 1015 cm−3 for B = 0 to B = 374 mT, respectively. Analytical results from the plasma treated water provided that the electrical conductivity (EC), oxidative reduction potential (ORP), and the concentrations of O3 and H2 O2 enhanced from 155 to 229 µS cm−1, 141 to 17 mV, 1.34 to 1.92 mg L−1, and 5.61 to 10.92 mg L−1 due to the influence of axial DC magnetic field, while pH reduced from 5.10 to 3.93 for 30 min treatment of water with B = 0 and B = 374 mT, respectively. The model wastewater prepared with Remazol brilliant blue textile dye and the plasma treated wastewater studied by optical absorption spectrometer, Fourier transform infrared spectrometer, and gas chromatography mass spectrometer. The results show that the decolorization efficiency increased ~ 20% after 5 min treatment for the maximum B = 374 mT with respect to zero-magnetic field and, power consumption, and electrical energy cost reduced ~ 6.3% and ~ 4.5%, respectively, due to the maximum assisted axial DC magnetic field strength of 374 mT. [ABSTRACT FROM AUTHOR]

Tendon injuries can result in two major drawbacks. Adhesions to the surrounding tissue may limit the range of motion, while fibrovascular scar formation can lead to poor biomechanical outcomes. Prosthetic devices may help to mitigate those problems. Emulsion electrospinning was used to develop a novel three-layer tube based on the polymer DegraPol (DP), with incorporated insulin-like growth factor-1 (IGF-1) in the middle layer. Scanning electron microscopy was utilized to assess the fiber diameter in IGF-1 containing pure DP meshes. Further characterization was performed with Fourier Transformed Infrared Spectroscopy, Differential Scanning Calorimetry, and water contact angle, as well as through the assessment of mechanical properties and release kinetics from ELISA, and the bioactivity of IGF-1 by qPCR of collagen I, ki67, and tenomodulin in rabbit Achilles tenocytes. The IGF-1-containing tubes exhibited a sustained release of the growth factor up to 4 days and showed bioactivity by significantly upregulated ki67 and tenomodulin gene expression. Moreover, they proved to be mechanically superior to pure DP tubes (significantly higher fracture strain, failure stress, and elastic modulus). The novel three-layer tubes intended to be applied over conventionally sutured tendons after a rupture may help accelerate the healing process. The release of IGF-1 stimulates proliferation and matrix synthesis of cells at the repair site. In addition, adhesion formation to surrounding tissue can be reduced due to the physical barrier. [ABSTRACT FROM AUTHOR]

The tethering dynamics of PyridoPyrrole Quinoxaline (PPQ) anticancer with gold nanoparticles (AuNPs) forming the PPQ/AuNPs complex were investigated. PPQ was synthesized from various substituted nitro-fluoroquinolone and the resulting chemical structure was validated using high-resolution 1H- and 13C-NMR. The tethering in PPQ/AuNPs was activated by irradiating the samples with light at λ ~ 525 nm (surface plasmon resonance (SPR) of AuNPs) and simultaneously with electrical pulsing applied to the electrical electrodes. FTIR and UV–Vis spectroscopy as well as Density Functional Theory (DFT) modeling were used to obtain results on the PPQ/AuNPs with different PPQ concentrations. The results elucidate the formed intermolecular bonding between AuNPs with PPQ on the sites of fluorine atoms or/and hydrogen in the hydroxyl group. The absorbance spectra of PPQ/AuNPs revealed appearing new peaks at 300 nm, 386 nm, and 711 nm. FTIR spectrum was calculated using a DFT model based on tethered a single gold nanoparticle with four PPQ molecules in the fluorine sides where the optimized structure was a distorted tetrahedral geometry of bounded four PPQ molecules with AuNP as a center. The calculated FTIR spectrum was in excellent matching with the experimental FTIR spectrum. The calculated complexation energy was equal to − 3975.5 kcal/mole which is less than the sum of the energy of the PPQ (− 959.5 kcal/mol) and the AuNP (− 135.4 kcal/mol) indicating that tethering led to a stable complex. The binding energy of the PPQ/AuNPs complex deduced from the DFT calculations proved that the highest tethering stability which leads to the minimum energy is at the site of the fluorine atoms. [ABSTRACT FROM AUTHOR]

This paper studies the merits of applying liquified polyethylene (PE) as a modifier for bitumen. Chemical recycling of PE is often incomplete and generates some amount of waste "PE oil". The viscoelasticity and chemical characteristics of bitumen modified with PE oil were examined using dynamic shear rheometry, infrared spectroscopy, and adhesion measurements in comparison and in conjunction with bitumen modified with wax, which is one of the most common additives in warm-mix bitumen. The study found that PE oil softens bitumen without severely increasing the creep compliance or viscoelastic damping properties. Wax-modified bitumen showed enrichment of crystallized alkanes at the free bitumen surface that negatively impacted adhesion and interface healing. The introduction of PE oil to wax-modified bitumen did not appreciably decrease the fraction of crystallized wax. Thus, PE oil may not be effective as an additive for warm-mix wax-modified bitumen. However, the PE oil showed potential in protecting bitumen against ultraviolet (UV) aging, and it is worth further exploration as an anti-aging agent, or as a rejuvenator for reclaimed asphalt pavement. The outcomes of this study promote plastic recycling by presenting the merits of applications of liquefied waste PE in the design and engineering of bituminous composites. [ABSTRACT FROM AUTHOR]

Industrialization leads to the entry of diverse xenobiotic compounds into the environment. One such compound is paracetamol (APAP), which is emerging as a pharmaceutical and personal care pollutant (PPCP). In this study, the APAP degrading bacterium was isolated by enrichment culture method from the sewage sample. The microscopy, biochemical, and 16S rRNA gene sequence analyzed the isolate PPY-2, which belongs to Bacillus licheniformis, and GenBank assigned accession number MN744328. Physiological and batch culture degradation studies have indicated that the strain involved in the degradation of APAP. The optimum pH for degradation of the PPY-2 was 7.7, whereas the temperature was 25 °C, agitation speed was 142 rpm, and concentration of APAP was 621 mg/L reported, and the optimum temperatures were 42 °C and 32 °C, respectively. Biomass kinetic was studied at optimal physical conditions, which suggested that the specific growth rate (μ) was 721 mg/L. The GC–MS chromatogram peaks have detected metabolites, viz., oxalic acid, 2-isopropyl-5-methyl cyclohexanone, and phenothiazine. The study confirmed that Bacillus licheniformis strain PPY-2 exhibits metabolic potential to biodegradation APAP and can be further deployed in bioremediation. [ABSTRACT FROM AUTHOR]

In the present work, a novel purslane (Sesuvium portulacastrum) fiber has been identified and the effect of surface modifications on its physical, mechanical, and thermal properties has been studied. The fiber surface has been treated with different chemicals, such as sodium hydroxide, acrylic acid, maleic anhydride, potassium permanganate, and benzoyl peroxide. The density, water absorption property, mechanical properties, thermogravimetry analysis, Fourier transform infrared spectroscopy, and surface morphology have been thoroughly investigated. It has been observed that acrylic-acid-treated purslane fiber gives better performance in comparison to other treatments with an enhancement of 36.68% of tensile strength as compared to untreated fibers.

Currently more emphasis is given to plants originated fibers for many applications due to their potential use in solving emerging problems concerning the environment. This research is based on evaluation of fiber concentration and treatment on physical, mechanical and thermal properties of untreated and treated Prosopis Juliflora (PJ) bark fiber reinforced epoxy composites. Composites were fabricated with varying weight % (i.e 5%, 10%, 15%, 20% and 25%) of untreated and treated PJ bark fibers in epoxy resin using hand lay-up method. From the results obtained, it is obvious that the mechanical and thermal properties of composites reinforced with chemically treated fibers were enhanced due to fiber surface modification which helps in better bonding with matrix. Moreover, the composites with 20wt% fiber concentration shows good tensile strength, young’s modulus, impact strength and was found to be 84.22MPa, 3.94 GPa, 31.76 KJ/m2 and 59.18 MPa respectively. Finally, the failure analysis of fracture surface due to delimitation, pull-out of the fibers, percentage of voids and composite fracture has been verified using scanning electron microscope.

In this work, the use of agricultural waste from oil palm petioles (OPP) as a raw material for the production of activated carbon (AC) and its characterization were examined. By soaking these chars in nitric acid (HNO3) and potassium hydroxide (KOH) at a 10% concentration, AC with favorable high-porosity carbons was generated. To maximize AC synthesis, the AC was pyrolyzed at 460, 480, and 500 °C temperatures for 20 min. Based on micrographs of formed pores and surface functional groups, 480 °C carbonization temperature on both chemical HNO3 and KOH was shown to be the best. The FTIR measurements reveal that chemical activation successfully transformed the raw material into AC. Moreover, FESEM micrographs show the pores and cavities of the prepared AC achieve a high surface area. This is further supported by BET results of HNO3 OPP AC and KOH OPP AC with surface areas of 883.3 and 372.4 m2/g, respectively, compared with the surface area of raw OPP of 0.58 m2/g. Furthermore, the tests were revealed by an optimization model, namely response surface methodology (RSM), using a central composite design (CCD) technique. The findings showed that all three parameters (pH, time, and dose) had a substantial impact on the removal of Zn, Fe, and Mn. Analysis of variance (ANOVA) and analytical error indicated that the models were accurate, with a low error value and a high R2 > 0.9. Remarkably, the good correlation between actual and predicted removal values showed that the modified activated carbon is a promising adsorbent for heavy metal removal from wastewater. [ABSTRACT FROM AUTHOR]

Today, packaging is an integral part of any food product, preserving its quality and safety. The use of biodegradable packaging as an alternative to conventional polymers reduces the consumption of synthetic polymers and their negative impacts on the environment. The purpose of this study was to analyze the properties of a biodegradable compound based on polylactide (PLA) and polybutylene adipate terephthalate (PBAT). Test samples were made by blown extrusion. The structural, physical, and mechanical properties of the PLA/PBAT material were studied. The property variations during compost storage in the lab were monitored for 365 days. The physical and mechanical properties were measured in accordance with the GOST 14236-2017 (ISO 527-2:2012) standard. We measured the tensile strength and elongation at rupture. We used attenuated total reflectance Fourier transform infrared microscopy (ATR-FTIR) to analyze the changes in the material structure. This paper presents a comparative analysis of the strengths of a biodegradable material and grade H polyethylene film (manufactured to GOST 10354-82). PLA/PBAT's longitudinal and transverse tensile strengths are 14.08% and 32.59% lower than those of LDPE, respectively. Nevertheless, the results indicate that, given its physical and mechanical properties, the PLA/PBAT material can be an alternative to conventional PE film food packaging. The structural study results are in good agreement with the physical and mechanical tests. Micrographs clearly show the surface deformations of the biodegradable material. They increase with the compost storage duration. The scanning microscopy (SEM) surface analysis of the original PLA/PBAT films indicated that the PLA structure is similar to that of a multilayer shell or sponge, which is visible at medium and especially high magnification. We conclude that PLA/PBAT-based biodegradable materials are potential substitutes for conventional PE polymer films. [ABSTRACT FROM AUTHOR]

As state-of-the-art electrochemical energy conversion and storage (EECS) techniques, fuel cells and rechargeable batteries have achieved great success in the past decades. However, modern societies' ever-growing demand in energy calls for EECS devices with high efficiency and enhanced performance, which mainly rely on the rational design of catalysts, electrode materials, and electrode/electrolyte interfaces in EESC, based on in-deep and comprehensive mechanistic understanding of the relevant electrochemical redox reactions. Such an understanding can be realized by monitoring the dynamic redox reaction processes under realistic operation conditions using in situ techniques, such as in situ Raman, Fourier transform infrared (FTIR), and X-ray diffraction (XRD) spectroscopy. These techniques can provide characteristic spectroscopic information of molecules and/or crystals, which are sensitive to structure/phase changes resulted from different electrochemical working conditions, hence allowing for intermediates identification and mechanisms understanding. This review described and summarized recent progress in the in situ studies of fuel cells and rechargeable batteries via Raman, FTIR, and XRD spectroscopy. The applications of these in situ techniques on typical electrocatalytic electrooxidation reaction and oxygen reduction reaction (ORR) in fuel cells, on representative high capacity and/or resource abundance cathodes and anodes, and on the solid electrolyte interface (SEI) in rechargeable batteries are discussed. We discuss how these techniques promote the development of novel EECS systems and highlight their critical importance in future EECS research. [ABSTRACT FROM AUTHOR]

The superior performance of styrene-butadiene-styrene (SBS) modified asphalt makes it widely used in asphalt pavement construction. However, SBS-modified asphalt pavement still faces an aging problem. Aging causes the performance of asphalt materials to decline and many pavement diseases. The dosage of SBS commonly used in industry is generally between 3% and 4.5%, and the performance of SBS with a high dosage needs to be explored. Therefore, in this paper, 12 modified binders were prepared with blending amounts of 3%, 5%, and 7% and the type of modifiers as linear and star. The softening point increment (SPI), viscosity aging index (VAI), rutting factor index (RFI), complex modulus aging index (CMAI), and phase angle aging index (PAAI) were used to study the antiaging performance of SBS-modified asphalt. Fourier transform infrared spectroscopy (FTIR) and gel permeation chromatography (GPC) were used to study the microscopic and structural changes that occur during the aging process of modified asphalt. The result shows that when the amount of the same type of modifier is 3%–7%, the higher the amount of modifier, the better the performance of the modified asphalt. At the same content, a star modifier is not necessarily better than a linear modifier. For the same type of modifier, the larger the amount, the better the antiaging performance of the modified asphalt. Given an increase in aging time, the deterioration of the asphalt performance will deepen. Aging leads to the enhanced high-temperature performance of asphalt. The macroscopic performance of asphalt aging can be explained by the microscopic view. The aging process of modified asphalt is the cumulative process of oxidation products. [ABSTRACT FROM AUTHOR]

ObjectiveTo establish a method to identify unknown sample based on the combined use of Fourier transform infrared spectroscopy （FTIR）, gas chromatography-quadrupole time-of-flight mass spectrometry （GC-QTOF-MS）, ultra-high performance liquid chromatography-linear ion trap quadrupole-orbitrap mass spectrometry （UPLC-LTQ-Orbitrap MS） and 1H-nuclear magnetic resonance spectroscopy （1H-NMR） technique.MethodsThe unknown sample was directly analyzed by FTIR. The unknown sample was dissolved in methanol solution containing internal standard SKF525A and the supernatant was detected by GC-QTOF-MS and UPLC-LTQ-Orbitrap MS. The unknown sample was dissolved in methanol-d4 solution for structural analysis of 1H-NMR.ResultsThe characteristic absorption peaks of FTIR spectra obtained from unknown sample were 1 682 （C=O bond）, 1 503, 1 488, 1 436, 1 363, 1 256, 1 092, 1 035, 935, 840 and 800 cm-1, the characteristic fragment ions （m/z） of GC-QTOF-MS were 86.096 4 （base peak）, 58.065 1, 149.023 5, 121.028 6 and 65.038 6, the accurate mass [M+H]+ detected by UPLC-LTQ-Orbitrap MS was 236.127 7. The sample was identified as synthetic cathinone new psychoactive substance Eutylone by 1H-NMR.ConclusionThe method established in this study can be used for structural confirmation of Eutylone.

In order to study the secondary spontaneous combustion of coal treated with different pre-oxidation temperatures, pre-oxidized coals with different temperatures were prepared by temperature programmed device. The changes of functional groups of pre-oxidized coals were measured by Fourier transform infrared spectroscopy(FTIR). The thermal effect in the process of secondary spontaneous combustion of pre-oxidized coal samples was studied by differential scanning calorimetry, and the kinetic parameters of exothermic reaction were calculated. The results show that with the increase of pre-oxidation temperature, the characteristic temperatures in the process of coal secondary spontaneous combustion increase in varying degrees, and the heat absorption first increases and then decreases, while the maximum exothermic value, exothermic heat and activation energy in exothermic stage all show an upward trend, indicating that the exothermic reaction of coal is more intense after pre-oxidation. Pre-oxidation only changed the content of functional groups in coal, but did not affect the types of functional groups. After pre-oxidation, the -OH, -C=C- and -CH functional groups in coal decreased with the increase of pre-oxidation temperature, while -C-O-, -COOH, substituted benzene, -CH3 and -CH2- increased with the increase of pre-oxidation temperature. On the whole, after pre-oxidation, the active structure in coal increases and the risk of spontaneous combustion increases.

The acrylic acid treated rattan fiber reinforced epoxy (RF/Epoxy) composite has been fabricated by taking various weight percentages (5, 10, 15, 20, and 25 wt%) of fibers using hand layup followed by compression molding technique. The optimum fiber loading has been determined by regression analysis and it is found that 18 wt% of rattan fiber gives maximum tensile strength. The interaction of rattan fiber with epoxy matrix has been studied by Fourier transform infrared spectroscopy and X-ray diffraction. Scanning electron microscope (SEM) has been used to study the morphology of chemically modified rattan fiber and RF/Epoxy composite. The mechanical, thermal, and dynamic mechanical thermal properties of 18 wt% RF/Epoxy composite have been studied as per ASTM standards. From the results, it is observed that RF/Epoxy composite gives best properties at optimum (18 wt%) fiber loading. The maximum tensile strength and flexural strength of the composite are found to be 47.5 and 121 MPa, respectively, which is better in comparison to other natural fiber composites used for manufacturing different automobile body parts. Hence, it can be concluded that 18 wt% RF/Epoxy composite can be considered as a potential candidate for automotive body parts.

This research focuses on developing a new material by reinforcing chemically treated Eleusine Indica (EI) fiber with epoxy resin as matrix. Composites using varying wt% of treated EI fibers were fabricated taking epoxy as matrix. The effect of chemical treatment and fiber loading on various mechanical properties, thermal, and morphology using a scanning electron microscope (SEM) was investigated. From the results obtained, it is obvious that the mechanical and thermal properties of composites reinforced with chemically treated fibers were enhanced due to fiber surface modification which helps in better bonding with matrix. Moreover, the composites with 20 wt% fiber concentration shows good tensile strength, Young’s modulus, impact strength and was found to be 79.31MPa, 3.84 GPa, 32.24 KJ/m2 respectively. At this fiber loading the composites were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and thermogravimetric (TGA) and compared with untreated fiber reinforced composites and neat epoxy. Finally, the failure analysis of fracture surface due to delimitation, pull-out of the fibers, percentage of voids, and composite fracture has been verified using scanning electron microscope. The findings provide manufacturers and engineers with a general concept of how to employ the composites to make low-weight automotive parts for improved fuel efficiency.

IntroductionThis study reports the abundance and distribution of microplastics in tropical estuarine mangrove areas in Penang, Malaysia.MethodsSamples were collected by using a neuston net and Ponar grab at four study sites (Seberang Perai, Kuala Muda, Penaga and Balik Pulau).Results and DiscussionA total of 8775 pieces were collected from the four sites, with abundance in coastal surface water, coastal bottom sediment, and estuarine sediment ranging between 201 ± 21.214 - 1407 ± 124.265 pcs/L, 255 ± 22.368 - 350 ± 25.892 pcs/kg, and 430 ± 7.234 - 4000 ± 29.174 pcs/kg respectively. Seberang Perai was found with the highest microplastics abundance in all compartments while fragment is the dominant morphology throughout all study sites. Stereomicroscopic analysis showed that microplastics are of numerous colours and irregular in shape while Field Emission Scanning Electron Microscope (FESEM) observed severe surficial weathering. Polyethylene is the most common identified polymer type via Fourier Transform Infrared Spectroscopy (FTIR) analysis and inorganic chemical compounds such as dimethylmercury were detected which pose a threat to organisms and the environment. The overall outcome suggests that human activities play a significant role in microplastic input into the estuarine environment and that the dominant polymer type in respective study site are closely related to the nature of human activities. This baseline study presents fundamental knowledge on microplastic pollution in the estuarine environment of Penang and encourages similar research to be conducted in the future for pollution control and management.

Scytonemin is a yellow-brown ultraviolet screening compound present in the sheath of several cyanobacteria. In this investigation, biological crusts from various natural habitats were examined for the presence of the photoprotective compound scytonemin. Cyanobacteria such as Scytonema sp., Anabaena sp., Nostoc sp., Fischerella sp. and Lyngbya sp. were present in these biological crusts. Analysis of photosynthetic pigments such as Chl a and carotenoids was done by UV-VIS spectrophotometer. The Chl a and carotenoid contents were found to be maximum in Scytonema sp. isolated from the wall of the excavated area of Sarnath. Identification and characterization of scytonemin were done through High-Performance Liquid Chromatography (HPLC), Fourier Transform Infrared Spectroscopy (FTIR) and High Resolution Mass Spectrometry (HRMS). Scytonemin was present in all samples and HPLC chromatograms showed absorption maxima at 386 nm having retention time ranging from 5.3 to 5.9 min. It also absorbs significantly at 252, 278 and 300 nm. HRMS showed [M + H]+m/z: 545.1) divulged scytonemin. From the present study, it can be concluded that synthesis of photoprotective compound scytonemin counteracts the harmful effects of solar radiation which enable cyanobacteria to colonize and survive in extreme environmental conditions such as rocks and walls of buildings that face prolonged high intensity solar radiation. Scytonemin as strong UV-shielding and antioxidant molecule can be considered as a key ingredient in various pharmaceutical industries for the development of novel drugs and natural Sun protection cream. [ABSTRACT FROM AUTHOR]

Mesoporous silica nanoparticles were synthesized via the sol-gel method using hexadecyltrimethylammonium bromide (CTAB) micelles as a template and a similar method was used for amino-silica nanoparticle synthesis. Compositional and structural analysis of materials involved Fourier transform infrared (FTIR) and Raman spectroscopies. A comparative study of the two spectra revealed the distinctive pattern for the samples, such as a strong peak from 1030 to 1050 cm−1 in the FTIR spectra, characteristic of Si–O–Si stretching vibration and the specific pattern of silica between 90 and 500 cm−1 and 2880 and 2980 cm−1 in the Raman spectra. A point of interest in this study was the control of CTAB removal during the second stage of synthesis that was highlighted in the FTIR spectra by decreasing intensity or disappearance of the peaks 2850 and 2930 cm−1 for - CH2 absorption. The presence of – NH2 groups in the amino-silica was evidenced by the changes from 1000 to 1500 cm−1 and the sharp band at 2900 cm−1 in the Raman spectra. The peaks at 1050, 1230, 1421, and 1464 cm−1 are present only in the spectra of the amino-silica as well as the higher and sharp band around 2900 cm−1, unlike the pattern in the spectra of silica without amino groups. The two spectroscopic methods offer valuable information concerning the structure of silica and amino-silica. Moreover, thermogravimetric analyses were confirmed these findings and the stability of silica nanoparticles in solution was investigated. [ABSTRACT FROM AUTHOR]