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The decrease in availability of mineral oils and their environmental hazards created the need to search for alternate bio-based oils. The aim of this study is to investigate the friction and wear characteristics of kapok (Ceiba pentandra) oil as a bio-lubricant.

The wear and friction characteristics between steel-steel contact under lubrication were found using a pin-on-disk tribometer under different loads and sliding speeds, respectively. The corrosion and oxidation stability of the test lubricants were also analyzed. The worn surfaces of the specimen are analyzed with the help of an optical microscope. The obtained results were compared with palm oil and mineral oil (SAE20W 40).

From the investigation, it is found that the kapok oil possess a lower coefficient of friction and wear rate than palm and mineral oil. It is also found that the coefficient of friction varies proportionally and the wear rate varies inversely with the sliding speed as expected.

The present results confirm that the kapok oil can be used as an alternative lubricant to reduce the demand for mineral-based oil lubricants.

The purpose of this paper is to find the influence of retailer equity and perceived risk on attitudes toward private label brand (PLB) grocery products.

Retailer equity includes four variables: retailer awareness, retailer association, retailer perceived quality and retailer loyalty. The perceived risk factors include functional risk, financial risk and social risk. The attitude toward PLBs was taken as the dependent variable. The study was carried out by using a standardized questionnaire for all three constructs. The convenience sampling method was adopted to carry out data collection from customers of organized retail stores in the city of Coimbatore, in the state of Tamil Nadu, India. The relationship between the three variables was studied with structural equation modeling using IBM SPSS Amos software.

The study revealed that excluding the Financial Risk and the Social Risk, functional risk alone has significant influence over the PLB Attitude. The Retailer Equity variables, retailer perceived quality and retailer loyalty have positive influence on the PLB Attitude, while the other two variables do not show any influence. Retailer Awareness shows a negative influence over the social risk. Retailer Association does not show any influence on any of the three risk factors. Retailer perceived quality shows negative influence over the functional risk while retailer loyalty negatively influences social risk.

The research study was carried out in cities that are populous in the Indian state of Tamil Nadu. All the respondents came from three cities in Tamil Nadu, namely, Coimbatore, Tiruppur and Madurai. Hence, extending the findings of the study to other countries where organized retail penetration is deeper may be attempted with caution.

The study will offer managers in the retail industry some understanding of the risk-relieving factors in operation when buying grocery goods.

The research paper contributes to the literature concerning the role played by retailer equity and perceived risk factors on attitudes toward PLBs.

The study aims to investigate the influence of fabric hybridization, stacking sequences and matrix materials on the tensile strength and damping behavior of jute/carbon reinforced hybrid composites.

The hybrid composites were fabricated with different sequences of fabric plies in epoxy and polyester matrix using a hand layup technique. The tensile and vibration characteristics were evaluated on the hybrid laminated composite models using finite element analysis (FEA), and the results were validated experimentally according to ASTM standards. The surface morphology of the fractured specimens was studied using the scanning electron microscope.

The experimental results revealed that the position of jute layers in the hybrid composites has a significant influence on the tensile strength and damping behavior. The hybrid composite with jute fiber at the surface sides and carbon fibers at the middle exhibited higher tensile strength with superior damping properties. Further, it is found that the experimental results are in good coherence with the FEA results.

The less weight and low-cost hybrid composites were fabricated by incorporating the jute and carbon fabrics in interply configurations. The influences of fabric hybridization, stacking arrangements and matrix materials on the tensile and vibration behavior of jute/carbon hybrid composites have been numerically evaluated and the results were experimentally validated.

In the Bollywood film Crow's Egg (Manikandan, 2015), two Indian children eat crow eggs that they collect from trees (taking three out of four eggs and leaving one with the mother crow) because they cannot afford chicken eggs. Because their father is in prison, the children make money by selling pieces of coal that fall off trains to support their working mother. Interestingly, the film shows no images of school in the lives of the two children, aged about seven and 10, and their friends next to them. Unfortunately, there are millions of children in the world who have no room for school in their lives, and they are not just numbers, they are individuals.

This paper adopts a modified Taguchi approach to develop empirical relationships to the performance characteristics (output responses) in terms of process variables and demonstrated their validity through comparison of test data. The method suggests a few tests as per the orthogonal array and provides complete information for all combinations of levels and process variables. This method also provides the estimated range of output responses so that the scatter in the repeated tests can be assessed prior to the tests.

In order to obtain defect-free products meeting the required specifications, researchers have conducted extensive experiments using powder bed fusion (PBF) process measuring the performance indicators (namely, relative density, surface roughness and hardness) to specify a set of printing parameters (namely, laser power, scanning speed and hatch spacing). A simple and reliable multi-objective optimization method is considered in this paper for specifying a set of optimal process parameters with SS316 L powder. It was reported that test samples printed even with optimal set of input variables revealed irregular shaped, microscopic porosities and improper melt pool formation.

Finally, based on detailed analysis, it is concluded that it is impossible to express the performance indicators, explicitly in terms of equivalent energy density (E_0ˆ*), which is a combination of multiple sets of selective laser melting (SLM) process parameters, with different performance indicators. Empirical relations for the performance indicators are developed in terms of SLM process parameters. Test data are within/close to the expected range.

Based on extensive analysis of the SS316 L data using modified Taguchi approach, the optimized process parameters are laser power = 298 W, scanning speed = 900 mm/s and hatch distance = 0.075 mm, for which the results of surface roughness = 2.77 Ra, relative density = 99.24%, hardness = 334 Hv and equivalent energy density is 4.062. The estimated data for the same are surface roughness is 3.733 Ra, relative density is 99.926%, hardness is 213.64 Hv and equivalent energy density is 3.677.

Even though equivalent energy density represents the energy input to the process, the findings of this paper conclude that energy density should no longer be considered as a dependent process parameter, as it provides multiple results for the specified energy density. This aspect has been successfully demonstrated in this paper using test data.

The purpose of this paper is to systematically study the dynamic contact stress, frictional heat and temperature field of femoral head-on-acetabular cup contact pairs in a gait cycle.

In this paper, four common femoral head-on-acetabular cup contact pairs are used as the research objects, mathematical calculations and finite element simulations are adopted. The contact model of hip joint head and acetabular cup was established by finite element simulation to analyze the stress and temperature distribution of the contact interface.

The results show that the contact stress of the head-on-cup interface is inversely proportional to the contact area; high contact stress directly leads to greater frictional heat. However, hip joints with metal-on-polyethylene or ceramic-on-polyethylene paired interfaces have lower frictional heat and show a significant temperature rise in one gait cycle, which may be related to the material properties of the acetabular cup.

Previous studies about calculating the interface frictional heat always ignore the dynamic change process in the contact load and the contact area. This study considered the dynamic changes of the contact stress and area of the femoral head-on-acetabular cup interface, and four common contact pairs were systematically analyzed.

Aviation is not only one of the key contributors to the economy and social structure of the world but it is also an industry whose environmental impacts are being closely monitored. Aircraft efficiency and technological advancements have significantly reduced aviation noise and emissions in recent decades. Nevertheless, as the need for passenger and freight transportation grows, the aviation sector is becoming a primary source of environmental issues and a significant driver of global warming. This chapter focusses on environmentally sustainable aviation with a net-zero emission target. It also highlights sustainable aviation policies and collaborative initiatives in the aviation industry to meet the 2050 net-zero emission goal. While the industry's efforts have increased opportunities recently, the industry has also had to face several challenges to achieve the net-zero aviation target.

The purpose of this study is to apply an incompressible smoothed particle hydrodynamics (ISPH) method to simulate the Magnetohydrodynamic (MHD) free convection flow of a nanofluid in a porous cavity containing rotating hexagonal and two circular cylinders under the impacts of Soret and Dufour numbers.

The inner shapes are rotating around a cavity center by a uniform circular motion at angular rate ω. An inner hexagonal shape has higher temperature T_h and concentration C_h than the inner two circular cylinders in which the temperature is T_c and concentration is C_c. The performed numerical simulations are presented in terms of the streamlines, isotherms and isoconcentration as well as the profiles of average Nusselt and Sherwood numbers.

The results indicated that the uniform motions of inner shapes are changing the characteristics of the fluid flow, temperature and concentration inside a cavity. An augmentation on a Hartman parameter slows down the flow speed and an inclination angle of a magnetic field raises the flow speed. A rise in the Soret number accompanied by a reduction in the Dufour number lead to a growth in the concentration distribution in a cavity.

ISPH method is used to simulate the double-diffusive convection of novel rotating shapes in a porous cavity. The inner novel shapes are rotating hexagonal and two circular cylinders.

This study aims to fabricate an electrospun scaffold by combining radish (Ra) and cerium oxide (CeO₂) into a polyurethane (PU) matrix through electrospinning and investigate its feasibility for cardiac applications.

Physicochemical properties were analysed through various characterization techniques such as scanning electron microscopy (SEM), Fourier transforms infrared transforms analysis (FTIR), contact angle measurements, thermal analysis, atomic force microscopy (AFM) and mechanical testing. Further, blood compatibility assessments were carried out through activated partial thromboplastin time (APTT) and prothrombin time (PT) and hemolysis assay to evaluate the anticoagulant nature.

PU/Ra and PU/Ra/CeO₂ exhibited a smaller fibre diameter than PU. Ra and CeO₂ were intercalated in the polyurethane matrix which was evidenced in the infrared analysis by hydrogen bond formation. PU/Ra composite exhibited hydrophilic nature whereas PU/Ra/CeO₂ composite turned hydrophobic. Surface measurements depicted the lowered surface roughness for the PU/Ra and PU/Ra/CeO₂ compared to the pristine PU. PU/Ra and PU/Ra/CeO₂ displayed enhanced degradation rates and improved mechanical strength than the pristine PU. The blood compatibility assay showed that the PU/Ra and PU/Ra/CeO₂ had delayed blood coagulation times and rendered less toxicity against red blood cells (RBC’s) than PU.

This is the first report on the use of radish/cerium oxide in cardiac applications. The developed composite (PU/Ra and PU/Ra/CeO₂) with enhanced mechanical and anticoagulant nature will serve as an indisputable candidate for cardiac tissue regeneration.

The purpose of this work is to explore electrical properties of an electrochemical sensor designed for the detection of malachite green (MG) present in an aqueous solution.

The present sensor consists in the spatial coupling of a polymeric membrane and an ion-sensitive electrode (platinum electrode). The preparation of the polymeric membrane involves the incorporation of an ionophore (D2HPA), a polymer (polyvinylchloride [PVC]) and a plasticizer (dioctyl phthalate [DOP]). Several techniques have been used to characterize this sensor: the cyclic voltammetry, the electrochemical impedance spectroscopy and the optical microscopy. The sensibility, the selectivity and the kinetic study of a modified platinum electrode have been evaluated by cyclic voltammetry.

The obtained results reveal the possibility of a linear relationship between the current of reduction peaks and MG concentration. A linear response was obtained in a wide-concentration range that stretches from 10⁻⁵ to 10⁻¹³ mol L⁻¹, with a good correlation coefficient (0.976) and a good detection limit of 5.74 × 10⁻¹⁴ mol L⁻¹ (a signal-to-noise ratio of 3). In addition, the voltammetric response of modified electrode can be enhanced by adding a layer of Nafion membrane. Under this optimal condition, a linear relationship was obtained, with a correlation coefficient of 0.986 and a detection limit of 1.92 × 10⁻¹⁸ mol L⁻¹.

In the present research, a convenient, inexpensive and reproducible method for the detection of MG was developed. The developed sensor is capable of competing against the conventional techniques in terms of speed, stability and economy.