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This work provides a thorough examination of the biological impacts of silver nanoparticles (AgNPs) via in vitro and in vivo investigations. In vitro tests demonstrated a concentration- dependent reduction in cell viability, decreasing from 90% at 5 µg/mL to 50% at 25 µg/mL, with a substantial rise in reactive oxygen species (ROS) from 20% to 80%. The data indicate that AgNPs may possess cytotoxic effects. Moreover, apoptosis rates escalated from 5% to 18% with increasing doses of AgNP. In vivo investigations revealed significant alterations in hematological parameters, including a decrease in hemoglobin concentrations (from 15 g/dL to 11 g/dL), an elevation in white blood cell counts (from 8 x10³/µL to 12 x10³/µL), and a drop in platelet counts (from 250 x10³/µL to 200 x10³/µL) corresponding to escalating AgNP dosages. Histological studies demonstrated dose-dependent changes in organ tissues, especially the liver, with scores escalating from two to six. Tumor size reductions of 20%, 40%, and 60% were seen with low, medium, and high dosages of AgNPs, respectively. These results underscore the promise of AgNPs for biological applications, especially in tumor therapy. Nonetheless, comprehensive safety evaluations and accurate dosage optimization are required prior to their clinical use. This work highlights the potential biological uses of AgNPs while stressing the need of meticulous evaluation to guarantee their safe and effective incorporation into medical procedures.

During the design phase of engineering networks, a critical issue remains the selection of pipe diameters that minimize capital investments for transporting the heat carrier from the heat source to the consumers. Object of study: a pressurized pipeline of circular cross-section with a moving heat carrier. Subject of study: total monetary costs for transporting the heat carrier as a function of the chosen pipeline diameter. Objective of study: to determine the pipe diameter that achieves maximum cost savings for transporting the heat carrier under given design conditions. Research methods: theory of hydraulic calculation for circular cross-section pipelines and theory of heat transfer through a single-layer cylindrical wall under steady-state conditions. Research results: using an example from a centralized heating system pipeline section, it was established that for a mass flow rate of the heat carrier equal to 32.9 t/h, the optimal pipe size would be 76×3 mm (nominal diameter 70 mm). Under current tariffs for thermal energy (24.82 USD/Gcal) and electrical energy (6.65 USD/(MW⋅h)), the total monetary costs for transporting the heat carrier over a heating season would be 56.28 USD per 1 running meter of pipeline. In comparison, with a nominal diameter of 50 mm, the total costs amounted to 90.37 USD; with a diameter of 80 mm, the costs were 63.29 USD. The developed method for hydraulic design calculations is universal and can be applied in the design of engineering networks where the working medium is a moving heat carrier (steam or hot water).

Heat pipe is used to extract heat generated from a surface and applicable to cooling of the many components. Some of the main applications of heat pipes are space crafts, computer systems, permafrost cooling, heat exchangers and thermal storage sub systems. In this work, an experiment will be carried out with an indirect heat composite pipe located with different orientation, heat input and mass flow. Thermal resistance, heat transfer coefficient and thermal efficiency are determined, which are applicable for laptop cooling and solar heating. Heat input 25 to 150 watts, with orientation angles 0, 30, 45, 90 degrees, mass flow rate are 0.01kg/sec, 0.02kg/sec and 0.03kg/sec are considered.

In the research work, AISI 431 grade stainless steel were chosen to investigate the effects of vacuum annealing processes on reducing hardness and enhancing ductility. Although stainless steel of martensitic type are well known for their high hardness, wear resistance and they have limited applications due to high hardness properties. Chosen for this research work, vacuum annealing were carried out to temperatures of 740°C, 840°C and 940°C. The samples were prepared cylindrically to a dimension of 40 mm length and 10 mm diameter. An untreated material was kept aside for comparison.Vacuum annealing involves heating the material in a controlled environment to eliminate impurities and relieve internal stresses, resulting in reduced hardness and improved ductility. To evaluate the effect of wear on annealed material, a pin-on-disc wear test apparatus were used. The wear behavior of the annealed specimens were compared to the untreated material. It includes both the treated and untreated samples, were examined by using a scanning electron microscope (SEM) to obtain images of microstructure. The results of this research work contribute to the understanding of the annealing effects on martensitic stainless steels and provide insights into optimizing their properties for specific applications.

Aim of current study is to utilize different sustainable artificial intelligence (AI) tools to check the influence of test factors on erosion wear. Bottom ash is taken as erodent at different solid concentration while brass is considered as base material. The parameters involved are rotational speed (N), solid concentration (CW), and testing time duration (T). According to experimental results and analysis based on different AI tools , it is abundantly found that erosion wear have a significant dependency on parameters such as N, CW, T and the order of maximum erosion was found as N > CW >T. The rate of rotation speed (N) has been identified as the factor that has the greatest impact on the degree to which erosion wear occur. 3D analysis has been conducted for the maximum and minimum erosion wear condition. In order to verify the accuracy, four distinct methods are utilized; nonetheless, the accuracy of the regression analysis has been found more promising when compared to that of the Ridge, lasso and neural network methodologies.

PMMA Composites have become the most popular materials due to its excellent strength-to-weight ratio, graphite reinforced for engineering applications. Researchers have used a variety of reinforcements to enhance the mechanical and tribological characteristics of various polymer matrixes, including carbon fiber, glass fiber, and carbon-based nanoparticles, graphite, alumina, silica, silicon carbide, titanium oxide, bacterial cellulose, Nano-cellulose, and zirconium oxide.This project focuses on the characteristics of composites made with graphite reinforcements that are based on polymethyl methacrylate. Die casting was used to manufacture this reinforced composite. To enhance the mechanical qualities (impact strength and hardness), tribological parameters (slide distance, normal load, and sliding velocity are employed for wear rate). Therefore, in this study, greater focus has been placed on on PMMA-based composites with graphite reinforcement.

When the two materials are in contact in motion, wear rate of the materials taken an important role. Aluminium alloys used in many applications like automobile components, aerospace components, home appliances, machine tool components. Advanced aluminium alloys are used in aerospace components. In this project wear studies of advanced aluminium alloys are carried using pin-on-disc machine three processing parameters considered are Load, Time and Speed. Twenty seven samples ae been tested to find wear rate of aluminium alloys. A Taguchi method is applied to find optimization process parameters which are having minimum wear rate. Aluminium alloy 6082 has a medium strength and good corrosion resistance. It is the strongest alloy

The growing demand for high performance engine technology in the two-wheeler market segment has pushed the average speed of the motorcycle to a higher limit, which has already raised the danger of motorcycle accidents leading to serious knee and lower tibia injuries. Vehicle designers, testers, and validators undergo rigorous design, testing, and validation processes based on the highest criteria for strength, weight reduction, enhanced fuel efficiency, etc., but with the fewest requirements for a vehicle’s safety in an accident. The design of a leg guard for the popular Indian Pulsar 150 motorcycle. By changing the shape and material, a thorough investigation of strength is performed. We select three different materials, such as SS202, SS347, and SS440C. The leg guard for the pulsar was built, and its stress and deformation were assessed. The optimal configuration is selected from a total of six variants using the least weight and stress deformation.

This paper presents an investigation into the minimum quantity lubrication mode with Nano fluid during turning of titanium (TI6AL4V) alloy. In heavy cutting conditions, minimum quantity lubrication (MQL) has been observed, that, Nano-cutting fluids which have enrich thermal conductivity than base fluid, are begun to be used in MQL system. The addition of the required nano particle ratio to the base liquid is one of the most important issues that arise in this method. Therefore, this study aimed to find the optimum distribution rate of graphene nano particles having excellent properties and machining parameters. To do this, graphene nano particles were added to a vegetable-based cutting solution. Nano-cutting fluids were prepared in different volumetric concentrations. When turning of titanium (TI6AL4V) alloy, these Nano fluids were used in the MQL system. Three different parameters were added to the experimental design to study the performance of Nano fluids under several cutting conditions. i.e., speed, feed rate and depth off cut. Apart from this experimental design, three tests were carried out at each concentration ratio while keeping the machining parameters constant to clearly see the impact of concentration rates on surface roughness, flank wear. And crater wear. In addition, while chipping/fracture, were observed under all cutting conditions

Grade 630 martensitic precipitation hardening stainless steel has a combination of high hardness and strength after suitable heat treatment. The great advantage of this grade is that they are usually supplied in the condition treated with the solution and then aged to achieve a sufficient high strength. Chosen for this research work, AISI 630 stainless steel samples were subjected to salt bath nitriding process. Three samples were chosen in the shape of tapered cylindrical shapes with diameter of 10 mm and length of 40 mm. The specimens were subjected to 60 Minutes, 120 Minutes, 180 Minutes and named as SBN1, SBN2, SBN3 respectively. One untreated specimen is kept aside for the comparison purpose with the treated specimens. After the heat treatment process wear test were conducted by pin on disc wear test machine. Then the hardness test is carried out using the Rockwell hardness test. The microscopic images were taken using Scanning electron microscope. The results were compared and the best wear resistant material is chosen for the required application.

In industries, components have to operate under extreme prerequisites such as high load, speed, temperature and at a chemical environment. The materials are selected by commercial availability, cost and by considering by their properties like strength, hardness etc. AISI 904L is a high alloy stainless steel with low carbon content material having poor hardness on the surface and negative wear properties. Many of the engineering failures are due to fatigue, corrosion and poor wear resistance which are initiated in its surface. This causes cracks in the surface which reduces the life of the material. Also the surfaces of the materials are caused by severe thermal, chemical and shock loads. Chosen for this work, AISI 904L materials were subjected to plasma or ion - nitriding process and were treated to 3 different timing parameters like 24 hrs, 48 hrs and 72 hrs respectively, maintaining constant temperature of 650oC. Among the availability of other nitriding process like gas and liquid nitriding, plasma nitriding gives good dimensional stability, uniform treatment, less distortion, uniform case depth irrespective towards size and shape of the specimen. For analyzing the wear properties, a pin on disc machine is utilized making the pin to get weared on disc against a load of 100N at a speed of 1000 rpm. Finally the metallographic studies were done by Scanning Electron Microscopic analysis.

The conventional optimization process in Injection Moulding includes actual shop floor trials in which melt temperature, mould temperature, injection time, injection pressure, pattern, feeder size, shape and location cores, mould layout, gating etc. are changed in each iteration which involves high machining cost, tooling cost, modification cost, melting cost, and transportation cost as well as, materials, energy, time are wasted in each trial until and unless the required results are obtained. Water meter component (DN20 Vent) is designed in CREO 5.0, and then components are 3D printed to cross check the dimensions and also to confirm whether all the other components can be accommodated or not. Then the mould flow analysis will be performed on a water meter components using different materials and changing the processing parameters. The input processing parameters considered are melt temperature, mould temperature and injection time, whereas the responses are warpage, volumetric shrinkage, cycle time and quality prediction. Grey relational analysis is carried out to determine the optimum injection moulding processing parameters.. The effort has been made to minimize the warpage, volumetric shrinkage, cycle time and maximize the quality prediction mould cavity and core for the components are designed in CREO 5.0 and manufactured using P20 tool steel. Then the water meter components are manufactured by inputting the optimal processing parameters in injection moulding machine to achieve high productivity and quality.

The utilization of carbon and glass fiber composites is very extensive in the fields of aviation and automobiles. The strength to weight fraction of these composites is immense. Even though, the modern applications require a lot of improvement in strength. The addition of Nano fillers had brought about significant changes in mechanical properties of the composites. The present work aims at finding out the effects on mechanical properties of composites due to the addition of titanium oxide 10% + silicon dioxide 10% hybrid filler. Hand layup process is used for the fabrication of tensile and flexural test specimens which are prepared as per the ASTM standards. The tensile test specimen is D-638 type-iv and the flexural specimen is D-790. Epoxy is used as resin and forms the matrix whereas the carbon and glass fibers act as reinforcement. The comparison is made between the specimens with and without hybrid filler. Two specimens of each type are prepared to have repeatability. The tensile and flexural tests are carried on universal testing machine (UTE-10) and results were obtained. The results showed a significant improvement in tensile and flexural strengths of carbon composites and only flexural strength in glass fibers with hybrid filler.

Heat pipes are used to transfer heat, which are hollow cylindrical shape device filled with small amount of working fluid, which can change its phase. The rate of heat transfer in heat pipes compared to normal heat exchanging devices is more. Depending on the applications of heat transfer various heat pipes are being designed. Methanol fluid is used with 50% fill ratio. It is made of copper with outer diameter of 15.88mm and inner diameter of 14.88mm. It consists of a screen mesh made of copper powder inside it with thickness of 0.5mm. Due to heat input methanol changes its phase from liquid to vapor. The vapor loses its heat and changes its phase back to liquid in the condenser. At the condenser section the vapour gives up it heat and changes its phase from vapour to liquid. The screen mesh assists the flow of condensed working fluid through capillary action. Optimized the results by “Taguchi method” using “Minitab software”. The Thermal analysis was done with the optimum conditions, which were obtained as a result from the optimization method by Ansys Fluent software. Then finally compared the thermal parameters obtained from experiments with the Thermal analysis result. It is found the maximum heat transfer rate is optimized using meshed wick heat pipe conditions.

Vacuum assisted resin transfer molding (VARTM) is one of the manufacturing technique that is viable for production of fiber reinforced polymer composite components suitable for aerospace, marine and commercial applications. However the repeatable quality of the product can be achieved by critically fixing the process parameters such as Vacuum Pressure (VP) and permeability of the preform. The present investigation is aimed at studying the effect of permeability for production of Glass Fiber Reinforced Polyester (GFRP) components with consistent quality. The VARTM mould is made with an acrylic transparent top cover to observe and record the resin flow pattern. Six layers of randomly placed glass fiber under five different vacuum pressures VP1 = 0.013, VP2 = 0.026, VP3 = 0.039, VP4 = 0.053 and VP5 = 0.066 MPa were studied. The laminates produced by this process under the above mentioned conditions were characterized with ASTM D procedures so as to study the effect of these process parameters on the quality of the laminate. And as mentioned there is a considerable effect of permeability on the impact strength and the void content in the laminates under different vacuum pressures. SEM analysis of the impact tested fractured GFRP composites showed the bonding of fiber and matrix.