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The construction industry commonly employs concrete as a construction material, which sometimes may be subjected to fire exposure. It is important to adopt fire safety measures while planning and constructing such structures to ensure the safety of the occupants and the structural integrity of the concrete. So, determining its performance at elevated temperatures is of utmost importance. The main objective of this study was to investigate the impact of mineral incorporations, namely, nano bentonite clay (NBC) and nano fly ash (NFA), on the retained properties of concrete at normal (27°C) and at elevated temperatures. The feasibility of partly substituting ordinary Portland cement utilizing a mixture of NBC (0–5%) and NFA (0–50%) in concrete was assessed under the exposure to an elevated temperature ranging from 200 to 600°C. Several parameters were examined, including compressive strength, flexural strength, split tensile capacity, water penetration, loss of mass, ultrasound pulse velocity, and microstructure properties. After the experimental analysis, it was observed that the fire endurance was shown to be improved with the inclusion of nanoparticles (BC and FA). A reduction in the loss of mass by samples subjected to elevated heat was observed with the addition of nano bentonite and NFA. The mechanical strength results were obtained as maximum for the concrete specimens with 2% NBC and 20% NFA and further, the specimens performed better when exposed to elevated temperature as compared with normal concrete specimens. The microstructure of the concrete also upgraded with better impermeability owing to the use of NBC and NFA.

The usage of biodegradable materials is gaining mounting applications owing to the environmental problems created by petroleum-based synthetic materials. Agro-waste materials are finding more scope as reinforcement materials in polymer composites, mainly because of their cost-effectiveness and availability. The main aim of this research work is to utilize agro-waste material in the form of mango seed waste (MSW) as a reinforcing material with polyvinyl alcohol (PVA) to form biocomposite. The biocomposites were fabricated using the solution casting technique. The research work focuses on the influence of varying ultrasonication periods (0–20 min at 5-min intervals, i.e., 0, 5, 10, 15, and 20 min) on the properties of PVA/MSW biocomposites. The fabricated biocomposites were subjected to tensile test, fracture morphology, moisture absorption (MA), Fourier transform infrared spectroscopy, and thermogravimetric analysis. The results revealed that the material with the highest tensile strength was 3.95 MPa obtained with the 20-min ultrasonication sample. This value is 49% higher than that obtained in the sample without ultrasonication. The scanning electron microscopy analysis shows that the 20-min ultrasonication sample indicated a good distribution of MSW fillers in the PVA contrasted with the rest of the samples. The thermal stability of the samples treated with ultrasonication was found to be significantly higher than that of the untreated samples, whereas the MA value decreased with increasing ultrasonication time. It can be observed from the results that biocomposites can be a potential alternative to the synthetic materials used in packaging applications.

The carbon nanotube (CNT) is becoming more popular due to their low-density, high-strength etc. Among CNTs, multi-walled carbon nanotubes (MWCNTs) are gaining more importance due to their enhanced thermal and electrical conductivity. The present research is exploring the applicability of MWCNTs reinforced with AA2024-T351 alloys for electromechanical applications. This study is currently undertaken for using MWCNTs as a reinforcing particulate for the purpose to enhance the characteristics including low density, high strength, and hardness together with excellent thermal and electrical conductivity of the aluminum alloy matrices. Therefore, this article provides a state-of-the-art experimental approach to fabricate and furthermore, to evaluate the mechanical characteristics, microstructural analysis, and fatigue behavior of Al–Cu–Mg–T351/MWCNT composites under both the mechanical and thermal loading by utilizing powder technology processing route. The uniform dispersion of CNTs has been exposed using ball milling process. Results revealed that the MWCNTs provide extraordinary synergistic strength, enhances fatigue resistance, creep resistance, ductility, and other mechanical characteristics of the aluminum-based composites. The mechanical loading of the composite exhibited increased properties as compared to thermal-loaded aluminum-MWCNT composites. Findings conclude that the maximum hardness of 35Hv obtained for sintered AA2024-T351 and 45Hv for 0.5% MWCNT heat-treated samples indicate that the addition of MWCNT enhances the hardness which may be because CNT is evenly dispersed at the interfacial space. Maximum UTS of 105.21 MPa was obtained with 0.5% MWCNT for sintered composites. Microstructural analysis of the Al–Cu–Mg–T351/MWCNTs composite exhibits reasonably uniform distribution, void formation, and good interfacial bonding. X-ray Diffraction method patterns of fabricated composite shows that the CNT is present at 2β = 23.6 and 44.6°, whereas high peaks of aluminum are present at uniform dispersed positions. Transmission electron magnifying instrument study further substantiates the above research. Fracture micrographs of the Al–Cu–Mg–T351/MWCNTs composite portray the resistant nature of the nanotubes due to the presence of CNTs, Al–Cu, and aluminum carbide elements in the alloy and the reactions that happened during heat treatment. This significant improvement was attributed to the shear interactions among the constituents and high load carrying capacity of the CNT, uniform dispersion, and interface bond strength among the matrix and constituents. The findings in the study will undoubtedly be beneficial for the development of high-strength, MWCNTs/Al–Cu–Mg–T351, matrix composites in future for multifunctional applications on broader spectrum.

Introduction. Triphasic waves in an electroencephalogram (EEG) in patients with decreased alertness traditionally is associated with hepatic encephalopathy. The development of digital technologies and the introduction of systems that allow long-term EEG monitoring of the neurocritical care patients has led to accumulation of significant experience in recording triphasic waves in various metabolic, toxic, and structural brain disorders, as well as in nonconvulsive status epilepticus. Materials and methods. We present a case of diagnosis and successful treatment of a nonconvulsive status epilepticus, that developed in a female patient after CABG, and that presented electrographically as a triphasic wave pattern. Results. Description of the patients EEG according to the classification of rhythmic and periodic patterns of the American Clinical Neurophysiology Society and the use of clinical and EEG criteria of nonconvulsive status epilepticus of the International League Against Epilepsy enabled us to correctly diagnose the cause of her decreased alertness and other neurological symptoms. Proper selection of the antiepileptic drugs along with monitoring of daily EEG recordings led to a recovery of consciousness in the patient and to normalization of the EEG pattern, which confirmed the clinical hypothesis of a nonconvulsive status epilepticus. Conclusions. Utilization of the modern clinical and electrographic classifications enables the diagnosis of a nonconvulsive epileptic seizure and status epilepticus when the EEG pattern is ambiguous and traditionally associated with other conditions. EEG monitoring must be performed in patients with a sudden deterioration of consciousness that cannot be explained by brain imaging studies.

Edible film biocomposite (EFB) is a kind of materials able to substitute the non-biodegradable plastics. This idea is one of the breakthroughs in reducing plastic waste which is not environmentally friendly. EFB is an environmentally-safe and biocompostable material. This research explores and fabricate EFB from tapioca starch, soy lecithin and sugarcane bagasse fiber (SBF). The SBF was varied by 1, 2, and 3% (from dry starch) into the cassava starch/soy lecithin matrix. The production of EFB was solution casting. A tensile machine and Scanning Electron Microscope (SEM) observed the tensile properties and fracture surface characteristics. The results present that the highest value of tensile strength is in EFB (2% SBF) of 0.823 MPa. The tensile modulus shows a similar trend in values for this EFB of 0.523 MPa. In addition, the fracture surface provides information that a rough surface indicates a good bond between the matrix and the fiber. These two observations confirm that the matrix has successfully transferred the tensile load to the reinforcement. Meanwhile, the results of resistance to moisture resistance also experienced an increasing trend of around 4% from unreinforced specimens.