Rayat Bahra University

In this study, the comparison of rice husk ash (RHA)- and fly ash (FA)-based geopolymer mortar with traditional plaster of Paris and ordinary Portland cement mortars is carried out, which focuses on mechanical and durability properties as well as heat insulation. RHA and FA by-products from rice milling and thermal power plants are activated using an alkaline solution to create a geopolymer binder. Mortar specimens were made and tested for compressive, tensile, and flexural strength; density; water absorption; acid attack; and heat conductivity. The findings show that RHA-based geopolymer mortar has better heat insulation, similar strength, and high durability to FA-based mortar and conventional mortars, making it a promising material for sustainable construction.

Polymer Matrix Composites represent a new generation of engineering materials in which matrix materials are altered by reinforcing filler materials to enhance strength and other properties. In the present work, the Glass fiber reinforced polymer (GFRP) composites were fabricated by adding different compositions of Graphene as a Nano filler material using the Hand layup technique, followed by the Vacuum bagging process. The Graphene filler material was varied from 0 wt. %, 2 wt. %, and 4 wt. %. The prepared composites were characterized by subjecting them to various mechanical tests such as tensile test, flexural test, and micro hardness test. The experimental results revealed an increase in tensile strength by 5.48%, flexural strength by 27.74%, and a reduction in microhardness by 20% for 4 wt. % filler added GFRP compared to neat GFRP, indicating reduced brittleness and enhanced ductility. Furthermore, addition of graphene resulted in a 9% increase in elongation and improved interfacial bonding between glass fiber and epoxy matrix was observed. Scanning electron microscopy (SEM) analysis confirmed uniform graphene dispersion, reduced voids, and improved fiber-matrix adhesion. The results demonstrate that the inclusion of 4 wt. % graphene filler achieves an optimal balance between strength, flexibility, and interfacial bonding, making these composites suitable for structural and lightweight applications.

The increasing deployment of service robots in hotels has transformed traditional service encounters, necessitating a deeper understanding of tourists' acceptance intentions. Grounded in the Theory of Planned Behavior (TPB), this study investigates how attitudes, subjective norms, and perceived behavioral control shape potential tourists' intentions to use service robots for concierge and service delivery functions in hotels. Data were collected from 149 respondents in India using a structured online questionnaire measured on a seven-point Likert scale. Partial least squares structural equation modeling and Necessary Condition Analysis were employed for data analysis. The findings reveal that attitudes and subjective norms play a decisive role in shaping behavioral intentions, whereas perceived behavioral control exerts a weaker influence. The results highlight the socially embedded and evaluative nature of robot adoption decisions in hospitality contexts.

The convergence of robotics & smart hospitality in lodging operations is examined in this chapter, with a focus on how automation & artificial intelligence are changing housekeeping. It tracks the development of unsupervised service robots from manual & automated cleaning, focusing their operational responsibilities & contributions to consistency, efficiency & hygiene. It looks at the advantages & difficulties, as well as the technological, moral & social aspects of robotic implementation, using case studies from India & other countries. The chapter makes the case for a hybrid human & robot approach in which staff members may concentrate on client engagement & providing high quality service while repetitive activities are automated. Data driven, AI-powered, multitasking robots that easily connect with IoT systems are expected to become common in the future. In the end it comes to the conclusion that human & robot partnership, in which technology boosts productivity while maintaining the empathy and adaptation is crucial for hospitality & will be the key to the future of housekeeping.

A key factor in increasing the efficiency of perovskite solar cell (PCSs) is optimizing the thickness of the absorber and the operating temperature. In order to examine the impact of these factors, a planar n-i-p PSCs with the configuration FTO/α-Fe 2 O 3 /MAPbI 3 /Spiro-OMeTAD/Au was simulated using SCAPS-1D. The results indicate that the charge carrier generation and transportation are strongly governed by the thickness of MAPbI3 absorber layer. When tune to 600 nm thickness, the device has a Jsc of 22.1 mA/cm 2 , an Voc of 1.06 V, a FF of 77.4 %, and an overall PCE of 18.3 %. When layers are too thin (<300 nm), they limit the photon absorption, which lower the Jsc. When layers are too thick (>800nm), they cause recombination losses that lower the FF. Variation in the temperature also affect how well the device works in different temperature conditions. For example, raising form 300 K to 350 K lowers the Voc and PCE because of non-radiative recombination happens more often. These finding highlight that careful control of absorber thickness coupled with thermal stability of the α-Fe2O3 ETL is crucial for achieving stable and high-efficiency PSCs.

The present study is concerned with the synthesis of Schiff base functionalized organosilane via click reaction and eventually characterized via 1H and13C NMR, mass spectrum analysis and FT-IR spectroscopy. The...