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This study examines the sliding wear behavior of aluminium 7075 composites supplemented with crab shell ash (CSA), a waste product from the seafood industry. The composites with different weight percentages of CSA (0%, 1%, 2%, and 3%) were created using the stir-casting procedure. Afterward, a pin-on-disc device was used to evaluate these composites under different sliding conditions. The primary aim of this research is to analyze the effects of CSA content and sliding parameters on composite wear performance. In the experiment, it was discovered that the stability of the composites differed depending on the amount of CSA that was present. The unreinforced aluminum 7075 alloy's wear resistance was enhanced with CSA particles, according to the data. Wear resistance is optimal at 3% CSA content and begins to decline somewhat above this concentration. As a contribution to sustainable material engineering, this study is significant since it improves metal matrix composites' properties by reusing waste materials. This research emphasizes the potential of using waste materials such as crab shell ash to enhance mechanical properties and wear resistance, to promote sustainability in material engineering approaches.

Emerging contaminants (ECs) are substances that have been detected in water but have not been thoroughly tested or regulated. Pesticides, cosmetics, pharmaceuticals, and other medications are examples of compounds in this category. Even at low quantities, these pollutants can harm human health and the environment; therefore, avoiding them is critical. The consequences of EC pollution on the endocrine, hormonal, and genetic systems are causing significant concern. Even with current best practices and available technology, it is difficult to totally eliminate ECs from municipal and industrial wastewater treatment plants. Adsorption has been the method of choice for EC removal since it is less costly, more effective, and easier to use. To treat ECs, newer generation nanoadsorbents are employed. Adsorption was greatly enhanced by functional changes to the adsorbent surface. Carbon nanostructures are widely used as adsorbents because of their outstanding surface properties, adaptability, large surface area, adjustable structural changes, and high chemical stability. This review reviews and examines recent research on the production and use of carbon-based nanoadsorbents. The emphasis is on carbon nanotubes, graphene, and graphene-derived adsorbents. It is being investigated if these adsorbents can be used to extract hormone-disrupting chemicals and other emerging pollutants. The sources and classification of these pollutants, treatment knowledge gaps, and novel prospects for increasing carbonaceous nanoadsorbent utilization were all explored. The environmental and health problems associated with EC use are also studied.

A simple hydrothermal method is utilized to synthesize iron-doped tin oxide nanoparticles (Fe-SnO2 NPs) at various doping concentrations. The structural characterization using XRD, Raman, and FTIR measurements confirmed the incorporation of Fe ions into the SnO2 lattice without any deviation in the tetragonal crystal system of SnO2 nanoparticles. SEM and HRTEM images show the spherical-shaped nanoparticles with agglomeration. The values of interplanar spacing (d-value) calculated from the HRTEM lattice are consistent with the XRD results. Further, optical analysis revealed a red shift in the optical absorption band and a decrease in the band gap energy with an increase in Fe-dopant concentration. The decrease of PL emission peak intensity with Fe doping revealed the generation of singly charged oxygen vacancies. The H2O2-assisted photocatalytic degradation efficiency of Fe-SnO2 NPs investigated against crystal violet dye indicated an efficiency of 98% for 0.05 M Fe-SnO2 NPs within 30 minutes under visible light illumination. In addition, the effects of pH, scavengers, and reusability of the catalyst are tested. The antibacterial behavior of Fe-SnO2 NPs against Escherichia coli is examined by using the colony count method, and the inhibition rate was found to be 49, 65, 70, and 78% for pure, 0.01, 0.03, and 0.05 M Fe-SnO2 NPs, respectively.

The outer sphere electron transfer reaction of surfactant cobalt(III) complexes, Cis-[Co(en)2(4CNP)(C12H25NH2)](ClO4)3 1, Cis-[Co(trien)(4CNP)(C12H25NH2)](ClO4)3 2 and Cis-[Co(trien)(4AMP)(C12H25NH2)](ClO4)3 3 (en: ethylenediamine, trien: triethylenetetramine, 4CNP: 4-cyanopyridine, 4AMP: 4-aminopyridine, C12H25NH2: dodecylamine) have been investigated by Fe2+ ion in liposome vesicles (DPPC) and ionic liquids medium at different temperatures under pseudo first order conditions using an excess of the reductant. In the presence of ionic liquid medium the second order rate constant for this electron transfer reaction was found to increase with increasing concentration of ionic liquids. Below the phase transition temperature of DPPC, the rate decreased with increasing concentration of DPPC, while above the phase transition temperature the rate increased with increasing concentration of DPPC for the same complexes has also been studied. Experimentally the reactions were found to be second order and the electron transfer postulated as outer sphere. The results have been discussed in terms of increased hydrophobic effect, self aggregation and the presence of pyridine ligand containing 4-amino and 4-cyano substituent. Keywords: Surfactant cobalt(III) complex, Vesicles, Electron transfer, Hydrophobicity, Ionic liquids, Aggregation

The present requirement of automobile industry is seeking lightweight material that satisfices the technical and technological requirements with better mechanical and tribological characteristics. Aluminium matrix composite ( AMC ) materials meet the requirements of the modern demands. AMCs are used in automotive applications as engine cylinders, pistons, disc and drum brakes. This paper investigates the effect of particle size and wt% of Al2O3/SiC reinforcement on mechanical and tribological properties of hybrid metal matrix composites (HMMCs). AA2024 aluminium alloy is reinforced with Al2O3/SiC different particle sizes (10, 20 and 40 µm) and weight fractions (upto 10 wt %) were fabricated by using squeeze casting technique. HMMCs were characterized for its properties such asX-ray diffraction (XRD), density, scanning electron microscope ( SEM ), hardness, tensile strength, wear and coefficient of friction. AA2024/5wt%Al2O3/5wt%SiC with 10 μm reinforced particle size showed maximum hardness and tensile strength 156.4 HV and 531.43 MPa and decrease in wear rate was observed from from 0.00307 to 0.00221 for 10N. Hybrid composites showed improved mechanical and wear resistance suitable for engine cylinder liner applications.

Three dimensional numerical investigations has been carried out on steel lamp post against vehicle impact using ABAQUS/Explicit finite element code. The response of steel pole was studied against vehicle impact subjected to varying speed and mass of vehicle, and varying thickness and impact location of pole. The geometry of steel pole was considered on the basis of Indian standard recommendations and choice of pole is based on conventional highway lighting applications supporting luminaire mounting heights. The constitutive and fracture behavior of steel pole has been predicted using JC model available in ABAQUS/Explicit and the material parameters of JC model for the available in literature. The response of metallic pole was studied against varying speed, mass of vehicle and impact location considering the influential factors which affects the pole significantly. In addition to that, the response of pole was studied against the varying thickness, i.e. the effective thickness of cylindrical pole may be decreased at later stage due to corrosion and environmental effects. The responses of steel pole have been studied and presented in light of reaction forces, deflection and Von-Mises stresses.

Background The COVID-19 pandemic is found to affect the mental health of the population. Undergraduate medical students are especially prone to mental health disorders and hence could be more vulnerable to the impact of the pandemic. Methods A prospective longitudinal study was conducted on 217 undergraduate medical students in a medical college at Chennai, India. Depression, anxiety, and stress levels were recorded using Depression Anxiety Stress Scale 21 Items (DASS21) before and during the COVID-19 outbreak in India in December 2019 and June 2020, respectively. In the follow-up survey, in addition to DASS21, the Pittsburgh Sleep Quality Index to assess sleep quality and a self-administered questionnaire to assess the impact of COVID-19 related stressors were used. The self-administered questionnaire assessed the status of COVID-19 testing, interactions with COVID-19 patients, self-perceived levels of concerns and worries related to academics (COVID-19-AA (academic apprehensions)) and those pertaining to the self and family/friends (COVID-19-GA (general apprehensions)). Cross-sectional and longitudinal comparison of overall scores of depression, anxiety, and stress and scores stratified by gender, year of study, place of residence and monthly family income were performed. Predictors for depression, anxiety, and stress during COVID-19 were investigated using adjusted binary logistic regression analysis and results were expressed as adjusted odds ratio with 95% confidence interval (CI). A P value < 0.05 was considered statistically significant. Results The average scores of depression, anxiety, and stress during the baseline survey were 7.55 ± 7.86, 4.6 ± 6.19 and 7.31 ± 7.34 with the prevalence (95% Cl) of 33.2% [27–39.9%], 21.2% [16–27.2%] and 20.7% [15.5–26.7%]; in follow-up survey, the mean scores were 8.16 ± 8.9, 6.11 ± 7.13 and 9.31 ± 8.18 with the prevalence being 35.5% [29.1–42.2%], 33.2% [27–39.9%] and 24.9% [19.3–31.2%] for depression, anxiety, and stress respectively. There was a significant increase in both the prevalence and levels of anxiety and stress (P < 0.001), with depression remaining unchanged during COVID-19, irrespective of gender, year of study, place of residence and family’s monthly income. Poor sleep quality, higher levels of baseline depression, anxiety, and stress, higher COVID-19-GA, COVID-19 patients in family/friends and direct interactions with COVID-19 patients were found to be significant predictors of negative mental health in undergraduate medical students. COVID-19-AA was not significantly associated with depression, anxiety, and stress. Conclusion The COVID-19 pandemic appears to negatively affect the mental health of the undergraduate medical students with the prevalence and levels of anxiety and stress being increased, and depression symptoms remaining unaltered. Addressing and mitigating the negative effect of COVID-19 on the mental health of this population is crucial.

Energy efficiency is a crucial issue in wireless body area networks where energyconstrained sensor nodes are employed. In this paper, an energy model for multilevel quadrature amplitude modulation based wireless body area network is proposed and its energy efficiency is investigated. To improve the energy efficiency further, Rate Optimized scheme and Optimum Energy Consumption using Receive Diversity scheme are proposed. In Rate Optimized scheme, the data rate is varied according to transmission distance to ensure minimum total energy consumption. The Optimum Energy Consumption using Receive Diversity scheme utilizes receive diversity along with rate optimization. The total energy consumption of the proposed schemes is analysed. An energy saving of 53.16% at a distance of 7 m is achieved by the Optimum Energy Consumption using Receive Diversity scheme over conventional fixed rate scheme. However, the total energy consumption is still higher than multi-level phase shift keying based wireless body area network. The proposed Optimum Energy Consumption using Receive Diversity scheme is extended to multi-level phase shift keying based wireless body area network and achieved an energy saving of 22.44% and 22.31% over conventional fixed rate and Rate Optimized scheme at a transmission distance of 2 m.

The pharmacodynamic activity on the organic structure of benzoyl peroxide has been analysed by molecular spectroscopical tools (IR, Raman, nuclear magnetic resonance and UV–visible). Simultaneously, the results obtained in the experimental process are verified by performing Quantum Gaussian computational calculations with higher-order basis sets. The actual positions of internal compositions and purity of the compound are verified with the observations of fundamental and group frequency of the recorded pattern of the FT-IR and FT-Raman spectra. The chemical environment of different carbons existing in various entities for approving a drug property is keenly identified and distinguished. The energy level degeneracy among different Frontier molecular orbitals is viewed from the orbital overlapping interaction contour. The biological activity of the present compound is emphasized and correlated with the hyperpolarizability profile of the internal coordinate system of a molecular structure arrangement. The involvement of non-bonding molecular orbital for the inducement of drug reactivity is monitored from the observation of cluster electron transitions. The Gibbs energy for chemical reaction with augmented temperature is relatively discussed, and the continuum of chemical reaction is observed.

A key research subject in the area of unmanned aerial vehicles (UAVs) is how to make them autonomous. Towards this goal, the most vital step is stabilizing the attitude of the vehicles. This paper presents the design of an autonomous control system for a hybrid UAV to enable it to carry out a stable hovering mission under external wind disturbances. The hovering capability of the hybrid UAV under windy conditions is analysed with computational fluid dynamics (CFD) and a control law is designed to stabilize the craft in the hovering position. The proposed hovering controller is verified with simulations and experiments. Finally, the flight control system is installed in a small prototype and a full transition flight test, including vertical take-off, transition from vertical flight to cruise, cruise, transition cruise to vertical mode and hover landing, is successfully accomplished.

Background: Patello femoral Osteoarthritis is the most common degenerative disease in older age group, causing pain, physical disability, and decreased quality of life.As many treatment options available, kinesiotaping is an efficacious treatment for management of pain & disability in patellofemoral joint osteoarthritis. Previous studies have shown that kinesiotaping as well as quadriceps strengthening significantly yields functional benefits. But there is lack of evidence revealing combined effectiveness & effects of kinesiotaping along with quadriceps strengthening in subjects with patellofemoral joint osteoarthritis. Methods: 30 subjects with symptoms of patellofemoral osteoarthritis fulfilled the inclusion criteria were randomly assigned into 2 groups of 15 in each group. Taping along with quadriceps strengthening program is compared to the quadriceps strengthening program alone. Pain were measured by Visual Analogue Scale (VAS), knee ROM were measured by Goniometer, Functional status were measured by Western Ontario McMaster Universities index (WOMAC), score. Measurements were taken pre & post intervention. Results: The results indicated that kinesiotaping along with quadriceps strengthening exercises showed there was statistically significant improvement in pain (

In the title molecular salt, C16H10NO+·I−, the dihedral angle between the pyridinium and benzene rings is 6.61 (8)°. In the crystal, the cation is linked to the anion by a C—H...I interaction arising from the activated aromatic C atom adjacent to the N+ cation.

Four species of lice namely Columbicolacolumbae Menopon gallinae. Campanolotes bidentatus and Lipeurus caponis , two species of feather mites Megninia bakeri and Diplaegida columbae , an ixodid tick of Haemphysalissp. and the hippobseid Pseudolynchin canariensis were reported from 52 pigeons examined

Research was undertaken to explore the alteration of natural halloysite nanotubes (HNTs) using a blend of resorcinol and hexamethylenetetramine (RH), (γ-aminopropyl) triethoxysilane (APTES), and diethoxydimethyl silane (DMS). This investigation delved into the impact of incorporating various proportions of RH-modified HNTs (RH-HNTs), APTES- modified HNTs (APTES-HNTs), DMS-modified HNTs (DMS-HNTs), and unmodified HNTs into ethylene propylene diene monomer (EPDM) and nitrile butadiene rubber (NBR) for their potential as seal materials. The study assessed key properties such as tensile strength, stress at 100% elongation, elongation at break, compression set, hardness, and swelling and abrasion resistance to gauge the influence of HNT additions. As nanofiller content increased, the crosslinking rate rose, while scorch time and optimum cure time decreased. Findings indicated that incorporating nanofillers at 6 phr compositions notably enhanced composite strength initially, with a subsequent slight reduction. However, rebound resilience diminished with increasing filler content, though composite hardness experienced a slight improvement. Mole percent uptake decreased, particularly at higher filler loadings. Notably, systems containing 6 phr RH-HNTs exhibited a 140% increase in tensile strength. FESEM micrographs depicted a rough fracture surface with well-dispersed nanofillers within EPDM/NBR. Additionally, compression set data illustrated enhanced composite performance under compression, crucial for seal applications.