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Composite materials have distinct properties such as a high strength-to-weight ratio, high corrosion resistance, a high modulus-to-weight ratio and wear resistance. The potential, strong mechanical properties and lower cost of E-glass fiber motivated the authors to carry out this work. Tensile, flexural and Izod impact tests were used in the current study to conduct a static analysis of an E-glass-reinforced isophthalic polyester composite and an E-glass-reinforced general-purpose (GP) or orthophthalic polyester composite. The thermal–mechanical behavior was investigated using thermogravimetric analysis and dynamic mechanical analysis tests. Furthermore, the surface morphology of the tested composites was examined using scanning electron microscopy (SEM). When compared with the E-glass-reinforced GP polyester composite, the E-glass–isophthalic polyester composite demonstrated superior flexural properties and thermal stability. However, the tensile and impact properties of the E-glass–GP polyester composite were found to be higher than those of the E-glass–isophthalic polyester composite. SEM images show fiber pullout, matrix cracking and fiber breakage, among other things. The loss modulus and damping values of the E-glass-reinforced GP polyester composite were found to be greater than those of the E-glass-reinforced isophthalic polyester composite. The current composite can be used in marine applications, particularly the hull frame or body of the boat.

As the highest percentage of global mortality is caused by several cardiovascular diseases (CVD), maintenance and monitoring of a healthy cardiovascular condition have become the primary concern of each and every individual. Simultaneously, recent progress and advances in wearable pressure sensor technology have provided many pathways to monitor and detect underlying cardiovascular illness in terms of irregularities in heart rate, blood pressure, and blood oxygen saturation. These pressure sensors can be comfortably attached onto human skin or can be implanted on the surface of vascular grafts for uninterrupted monitoring of arterial blood pressure. While the traditional monitoring systems are time-consuming, expensive, and not user-friendly, flexible sensor technology has emerged as a promising and dynamic practice to collect important health information at a comparatively low cost in a reliable and user-friendly way. This Review explores the importance and necessity of cardiovascular health monitoring while emphasizing the role of flexible pressure sensors in monitoring patients' health conditions to avoid adverse effects. A comprehensive discussion on the current research progress along with the real-time impact and accessibility of pressure sensors developed for cardiovascular health monitoring applications has been provided.

High loadings of coarse alumina trihydrate (ATH), commercially used in polymers as a fire-retardant filler, cause uneven dispersion and reduce workability and affect physicomechanical properties. Better tensile properties can be achieved by uniform dispersion of nanosize ATH in polymers while maintaining its flame-retardant properties. Consequently, mechanical milling, being a sustainable approach towards the creation of nano-size materials, was carried out to reduce the particle size of coarse ATH in a high-energy planetary ball mill. Investigations were carried out to optimize the milling parameters such as time, rotational speed, milling media size and feed size. During milling, some of the physical properties of ATH change. The energy profile was studied to get the desired product properties. Nano-ATH within the PP matrix reduces the loadings with improvement in tensile and flexural strength. Hence, lightweight PP/nano-ATH composites for suitable use can be developed.

Improper handling of plastic waste and related chemical pollution has garnered much attention in recent years owing to the associated detrimental impacts on human health and the environment. This article reports an overview of the main interlinkages between persistent organic pollutants (POPs) and plastic in the waste management system of India. Both plastics and POPs share certain common traits such as persistence, resistance to biological degradation, and the ability to get transported over long distances. Throughout the processes of production, consumption, and disposal, plastics interact with and accumulate POPs through several mechanisms and end up co-existing in the environment. Plastic waste can undergo long-range transport through rivers and the oceans, break down into microplastics and get transported through the air, or remain locked in waste dump yards and landfills. Over time, environmental processes lead to the leaching and release of accumulated POPs from these plastic wastes. Plastic recycling in the Indian informal sector including smelting, scrubbing, and shredding of plastic waste, is also a potential major POPs source that demands further investigation. The presence of POPs in plastic waste and their fate in the plastic recycling process have not yet been elucidated. By enhancing our understanding of these processes, this paper may aid policy decisions to combat the release of POPs from different waste types and processes in India.

The present work studies the influence of zinc borate (ZB), magnesium hydroxide (MH) and ammonium polyphosphate (APP) as flame retardants on the curing, mechanical, thermal and flammability performances of Kevlar fibre (KF)-reinforced ethylene propylene diene monomer (EPDM) rubber composites. The flame retardant EPDM/KF composites were prepared with variable ratio of ZB, MH and APP. Thereafter, physicomechanical and thermal properties of the fire retardant EPDM/KF composites were analysed with density analysis, tensile testing, TGA analysis, SEM and cone calorimeter tests. The TGA analysis and cone calorimeter tests showed the enhancement in the flame retardant properties of the EPDM/KF composites with the addition of combined fillers with respect to the virgin counterparts. The synergistic effect of ZB and APP containing flame retardant-incorporated composites exhibited a prominence in the thermal stability and fire retardancy. Heat release rate (HRR) and total heat release rate (THR) of the ZB and APP combined fire retardant-incorporated composites were lower than the virgin EPDM.

Ostrinia nubilalis, a lepidopteran moth, also known as the European corn borer, has a major impact on the production of economically important crops in the United States and Europe. The female moth invites the male moth for mating through the release of pheromones, a volatile chemical signal. Pheromone binding proteins (PBPs) present in the male moth antennae are believed to pick up the pheromones, transport them across the aqueous sensillum lymph, and deliver them to the olfactory receptor neurons. Here we report for the first time the cloning, expression, refolding, purification, and structural characterization of Ostrinia nubilalis PBP3 (OnubPBP3). The recombinant protein showed nanomolar affinity to each isomer of the Ostrinia pheromones, E- and Z-11-tetradecenyl acetate. In a pH titration study by nuclear magnetic resonance, the protein exhibited an acid-induced unfolding at pH below 5.5. The molecular dynamics simulation study demonstrated ligand-induced conformational changes in the protein with both E- and Z-isomers of the Ostrinia pheromone. The simulation studies showed that while protein flexibility decreases upon binding to E-pheromone, it increases when bound to Z-pheromone. This finding suggests that the OnubPBP3 complex with E-pheromone is more stable than with Z-pheromone.

Ostrinia furnacalis is an invasive lepidopteran agricultural pest that relies on olfaction for mating and reproduction. Male moths have an extremely sensitive olfactory system that can detect the sex pheromones emitted by females over a great distance. Pheromone-binding proteins present in the male moth antenna play a key role in the pheromone uptake, transport, and release at the dendritic membrane of the olfactory neuron. Here, we report the first high-resolution NMR structure of a pheromone-binding protein from an Ostrinia species at pH 6.5. The core of the Ostrinia furnacalis PBP2 (OfurPBP2) consists of six helices, α1a (2-14), α1b (16-22), α2 (27-37), α3 (46-60), α4 (70-80), α5 (84-100), and α6 (107-124) surrounding a large hydrophobic pocket. The structure is stabilized by three disulfide bridges, 19-54, 50-108, and 97-117. In contrast to the unstructured C-terminus of other lepidopteran PBPs, the C-terminus of OfurPBP2 folds into an α-helix (α7) at pH 6.5. The protein has nanomolar affinity towards both pheromone isomers. Molecular docking of both pheromones, E-12 and Z-12-tetradecenyl acetate, to OfurPBP2 revealed that the residues Met5, Lys6, Met8, Thr9, Phe12, Phe36, Trp37, Phe76, Ser115, Phe118, Lys119, Ile122, His123, and Ala128 interact with both isomers, while Thr9 formed a hydrogen bond with the acetate head group. NMR structure and thermal unfolding studies with CD suggest that ligand release at pH 4.5 is likely due to the partial unfolding of the protein.

Alteration of the optical and photoelectrical properties of the photoanode materials are a prerequisite for improving the performance of dye-sensitized solar cell (DSSC). In this work, Ag-decorated cauliflower-like TiO2 photoanode was fabricated and studied the photovoltaic performance. The hierarchical structured TiO2 with abundant bundles exhibited a novel matrix for Ag deposition by the photoreduction technique. It is significant that the Ag nanoparticles showed a uniform size distribution on hierarchical structured TiO2 nanorods (HNRs). The plasmonic particle enfolded photoanode-based DSSC exhibited an efficiency of 4.15%, which is higher compared to the pristine TiO2 HNR (3.83%). The progress in the efficiency of plasmon particle-based DSSC is crucial, regarding the optical properties, and reduced charge transport resistance observed from the UV visible analysis (UV-Vis) and electrochemical impedance spectra (EIS).

Polypropylene (PP)/sisal fibre (SF)/carbon fibre (CF) hybrid composites were prepared by melt blending process at a variable weight percentage (wt%) of carbon: sisal fibre loading (20:10, 15:15, 10:20, and 5:25). MA-g-PP (MgP) as a compatibiliser was used to improve the dispersion of the fibres within the PP matrix. The composites were subjected to mechanical tests to optimize the fibre content of CF: SF. Incorporation of 20 wt% of CF and 10 wt% of SF with 5 wt% MgP resulted in higher mechanical performance of about 67.02 and 112% over that of PP/SF composite. Similarly, the impact strength was found to be optimum which enhanced to the tune of 39.62% as compared with PP/SF composites. Halpin Tsai model was used to compare the theoretical tensile modulus of PP/SF/MgP composites and PP/SF/CF/MgP hybrid composites with experimental evaluated values. Fracture toughness parameters such as K IC (critical stress intensity factor) and G IC (critical strain energy release rate) are determined for PP/SF/MgP composites and PP/SF/CF/MgP hybrid composites and compared by using single edge notch test. DSC study showed higher melting temperature (T m ) of PP/SF/CF/MgP composites as compared to PP revealing the enhancement in thermal stability. TGA/DTG study revealed the synergistic effect of the hybrid composite thus confirming the hybridisation effect of the system. DMA study showed that the hybridisation of CF and SF within the matrix polymer contributes to an increase in the storage modulus (Eʹ). Morphological observation by SEM confirmed that the carbon fibres and sisal fibres are well uniformly dispersed within the PP matrix, in the presence of MgP.

Purpose The purpose of this study is to reduce the application of petroleum in automobile paint industry by replacing it with bio-based castor oil along with nano fillers to synthesize automobile base coat (BC). Design/methodology/approach Bio-based polyurethane (PU) coating applicable in automobile BC was synthesized by using modified castor oil incorporated with nano silica (NS) and titanium-based pigment particles. The influential characteristics of the coating was studied by carrying out cross-cut tape test, abrasion resistance, pencil hardness, lap-shear, thermo gravimetric analysis, differential scanning calorimetry, dynamic mechanical analysis and acid, alkali and oil resistance tests. Findings Incorporation of NS particles, along with titanium-based pigment particles in optimized ratio into the paint matrix, increases the mechanical, chemical and oil resistance properties and hydrophobicity of the BC, and the findings are compared with the petro-based commercial BC. Research limitations/implications There is no significant improvement in thermal properties of the paint matrix, and it is less thermally stable than the commercial BC. Practical implications The paint developed through this study provides a simple and practical solution to reduce the petro-based feed-stock in automobile paint industry. Originality/value The current work which reports the use of ecofriendly PU BC for automobile paint applications is novel and findings of this study are original.

In printing electronics, graphene is used as a functional material due to its excellent physical properties. Therefore, to prepare a conductive graphene ink that contains non-toxic and environment-friendly solvent is very important. Direct preparation of graphene from graphite using liquid-phase exfoliation process is beneficial since it is simple and easy to use. Here in this work, we have synthesized the graphene dispersion using ethanol and water by liquid-phase exfoliation method and prepared a conductive graphene ink that shows an absence of coffee ring formation during the evaporation of solvents. A film has been prepared using the prepared ink which shows the electrical resistivity 1.06 Ω-cm at temperature 300 °C.

The comparative study of biodegradation of various blown films obtained from Poly (lactic) acid (PLA) has been studied via soil burial method. A total of 3-different types of films prepared from neat PLA and the reactive blends containing poly butylenes succinate-co-adipate (PBSA), and thermoplasticized starch (TPS); namely VPLA, PLA/PBSA, PLA/TPS respectively were the subjects of investigation. Several analytical techniques including weight loss method and analysis of mechanical properties were performed in each seven days interval until ninety days to elucidate the biodegradation in soil. The tensile modulus of VPLA and PLA/PBSA blown films were deteriorated to the tune of 60.32% and 71.28% respectively within 28 days, while PLA/TPS blown films recorded a significant reduction of 75.31% in the modulus value within 21 days of soil exposure compared to unexposed blown film samples. Similarly, blown films of PLA/TPS reported the highest rate of weight loss in the order of 40.06% in 90 days of soil burial with an estimated half-life of 103 days in soil environment compared to its counterparts. The depletion in both mechanical properties and weight of the film samples suggesting the occurrence of biodegradation in the real soil environment. Scanning electron microscopy (SEM) revealed the formation of coarse morphology for all three types of soil buried samples which trace of microbial action appeared on PLA/TPS films. Fourier transform infrared microscope (FTIR) showed the decrease in carbonyl index and variation in the intensities of carbonyl and hydroxyl peaks irrespective of the film samples after 90 days of soil exposure. Gel permeation chromatography (GPC) documented reduction in molecular weight and variation in polydispersity index (PDI) of post-exposed soil samples. The elemental analysis exhibited that the percentage of organic carbon and hydrogen content of all the films decreased while the oxygen percentage increased after soil burial due to the biodegradation of film specimens. Both Differential scanning calorimetry (DSC) and X-ray diffraction analysis (XRD) reported increase in crystallinity for soil exposed samples indicating the initiation of degradation kinetics preferably at the amorphous region of film composition. It has also been inferred that the biodegradation mechanism of VPLA and PLA/PBSA blown films predominantly driven by hydrolysis of ester bond. Contrastingly, the biodegradation kinetics in case of PLA/TPS film has been proceeded with microbial assimilation of TPS component which further thrived on hydrolysis of PLA component of the blown film system.

Asparagine-linked glycosylation, also known as N-linked glycosylation, is an essential and highly conserved co- and post-translational protein modification in eukaryotes and some prokaryotes. In the central step of this reaction, a carbohydrate moiety is transferred from a lipid-linked donor to the side-chain of a consensus asparagine in a nascent protein as it is synthesized at the ribosome. Complete loss of oligosaccharyltransferase (OST) function is lethal in eukaryotes. This reaction is carried out by a membrane-associated multisubunit enzyme, OST, localized in the endoplasmic reticulum. The smallest subunit, Ost4, contains a single membrane-spanning helix that is critical for maintaining the stability and activity of OST. Mutation of any residue from Met18 to Ile24 of Ost4 destabilizes the enzyme complex, affecting its activity. Here, we report solution nuclear magnetic resonance structures and molecular dynamics (MD) simulations of Ost4 and Ost4V23D in micelles. Our studies revealed that while the point mutation did not impact the structure of the protein, it affected its position and solvent exposure in the membrane mimetic environment. Furthermore, our MD simulations of the membrane-bound OST complex containing either WT or V23D mutant demonstrated disruption of most hydrophobic helix–helix interactions between Ost4V23D and transmembrane TM12 and TM13 of Stt3. This disengagement of Ost4V23D from the OST complex led to solvent exposure of the D23 residue in the hydrophobic pocket created by these interactions. Our study not only solves the structures of yeast Ost4 subunit and its mutant but also provides a basis for the destabilization of the OST complex and reduced OST activity.

The major roadblock for recycling of waste electrical and electronic equipments (WEEE) depends on the viability of sorting process, which is a complex task, involving various techniques such as sink float, froth flotation, optical separation and manual separation, etc. This makes the sorting process highly time consuming and expensive. The primary aim of this investigation is to study the properties of polymeric blends formulated from computer keyboards, by avoiding high end sorting procedure to avoid manpower and instrumental cost. The major polymers recovered from waste keyboards were identified as acrylonitrile butadiene styrene (ABS), high impact polystyrene (HIPS) and polystyrene (PS), using fourier transform infrared (FTIR) spectroscopy. These polymers were subjected to mechanical recycling by employing melt blending technique, followed by injection moulding. A ternary blend was prepared utilizing various percentages of ABS, HIPS and PS. The mechanical test of the blends revealed an optimum tensile strength of 35 ± 3 MPa, flexural strength of 65 ± 3 MPa, and impact strength of 45 ± 3 J/m. The homogeneity of the blends was determined through thermal analysis and morphological analysis of impact fractured specimens. The thermogravimetry analysis (TGA) showed a narrow peak with degradation of 98% of the blends at 700 °C. It was observed that, the properties of blends were similar to each other, which allows to eliminate multiple sorting process reducing cost aspect with improve performance characteristics.