TiO2 plays a significant role in many applications including solar cell. Consecutively to absorb the low-energy radiation, it is very much essential to tune the optical property of TiO2. We fabricated CeO2-ZnO-TiO2 semiconductor composites by sol-gel method and achieved the absorption of lower energy radiation. The prepared composites were characterized by TG-DTA, UV-DRS, XRD, AFM, TEM and FESEM techniques. The particle and crystalline size of the composites was calculated using FESEM and XRD techniques, respectively. The photocatalytic activity of the synthesized composite for the degradation of Rhodamine B (RhB) under visible light irradiation was investigated. The photocatalytic degradation of RhB under various experimental conditions such as amount of catalyst, initial dye concentration and H2O2 amount was also demonstrated and the rate constant was calculated using L-H model.

Abstract. Three types of shear stud arrangement, respectively featuring an orthogonal, a radial and a critical perimeter pattern, were evaluated numerically. A numerical investigation was conducted using the finite element software ABAQUS to evaluate their ability to resist punching shear in a flat plate. The finite element analysis here is an application of the nonlinear analysis of reinforced concrete structures using three-dimensional solid finite elements. The nonlinear characteristics of concrete were achieved by employing the concrete damaged plasticity model in the finite element program. Transverse shear stress was evaluated using finite element analysis in terms of shear stress distribution for flat plate with and without shear stud reinforcement. The model predicted that shear studs placed along the critical perimeter are more effective compared to orthogonal and radial patterns.

Many researchers have proposed different schemes of fiber reinforced polymer (FRP) wrapping to strengthen the Reinforced Concrete (RC) slab. However, the ideal system for FRP laminations is not readily available. A modular approach for strengthening of RC slabs (especially two-way slab) needs to be developed with respect to orientations and coverage area of FRP sheets in order to figure out the effective strengthening system. This paper describes the experimental study carried out to explore the effects of fiber reinforced polymers in different orientation and coverage areas to strengthen the structural members. Three systems of laminates have been used to strengthen the RC slabs using two types of fibers, namely carbon fiber reinforced polymer (CFRP) and glass fiber reinforced polymer (GFRP) composite. The systems are classified with respect to the orientation of FRP sheets such as edge, corner and center wrapping. Each system has three proportions of FRP coverage area in the order of 25%, 35%, and 45%. A set of fifty-four slabs were fabricated and tested at the rate of three specimens for each variant. The performance of the flexural strength of two-way RC slabs with different strengthening systems has been evaluated and compared. It shows that all the systems of strengthening are effectively enhancing the flexural strength of two-way RC slabs. The extent depends on the system orientation and coverage area of the FRP sheet. The higher-order performance is noticed when the FRP lamination has higher contact with the slab area and with closer proximity to the loaded area.

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A new model is reported to describe the dynamics of hydrodynamically induced breakdown of oil gel in pipes. Hitherto, the reported models (Davenport and Somper, 1971;Govier and Fogarasi, 1972; Rao et al. 1985a) cannot predict some observed inherent features of the breakdown process relating to its rates. The present model can predict these desiderata as well as delineate the effects of microscopic parameters such as size and shape of wax crystallites on the dynamics of breakdown. The model is based on a concept that energy imparted to the gelled structures is consumed in the breakdown process. Predictions of this model on breakdown time agree reasonably well with measurements. Important considerations relating to the amount of pressure head required for different diameters of pipe as well as for different dimensions of crystallites are analysed using this model.