Abstract Studies have shown that perovskites have a high potential of outdoing silicon based solar cells in terms of solar energy conversion, but their rate of degradation is also high. This study reports on improvement on the stability of CH3NH3PbI3 by passivating it with polymethylmethacrylate (PMMA). Structural and electronic properties of CH3NH3PbI3 stabilized by polymethylmethacrylate (PMMA) were investigated by varying concentrations of PMMA in the polymer solutions. Stability tests we...
Abstract: This study investigated the failure behaviour, energy absorption response and load carrying capability of fibre-glass (FG)/natural silk fibre (NS)/epoxy hybrid composite cylindrical tubes subjected to an axial quasi-static compression test. The reinforced cylindrical composite tubes were prepared using mandrel assisted hand lay-up technique. The specimen tested were three (3) fibre-glass cylindrical tube, each consisting of 5 layers of (FG); three (3) natural-silk fibre cylindrical...
Abstract: Zinc oxide (ZnO) is a naturally occurring n-type semiconductor which is viewed as a promising candidate to replace indium tin oxide (ITO) in opto-electric applications, owing to its natural abundance and a wide bandgap (3.37). Synthesis of ZnO thin films via chemical spray pyrolysis technique is more convenient and cost effective compared to the mostly used deposition techniques such as magnetron sputtering which are highly expensive. Chemical spray pyrolysis provide easier way of ...
This project work “Reliability analysis of a continuous beam using Hasofer-Lind Reliability Method” was primarily concerned with the effect of varying parameters such as load, modulus of elasticity, moment of inertia and span length on the reliability of a continuous beam. The limit state considered is deflection, and the allowable deflection is specified as L/360. The maximum deflection is 0.0069wL^4/EI and it occurs at 0.446L from either end (AISC, 1986). Reliability analysis, expre...
Linear analysis mostly applies to the problems that satisfy linear assumptions, materially linear problems that will have less displacements, less deformations, and boundary conditions which is constant. If any one of the above assumptions is not satisfied, a nonlinear analysis will have to be performed. ADINA Structures will provide powerful solving capacity and formulations which allows the solution of extremely complicated models with small CPU time and other memory requirements.
ABSTRACT In this work, models for predicting six structural characteristics and cost of sand-quarry dust blocks were developed. Three model equations namely Scheffe’s simplex lattice design (pseudo component), Scheffe’s simplex lattice design (component proportion) and Osadebe’s model were developed for each property. The properties investigated were Compressive strength, Water absorption and Split tensile strength. The others are Static modulus of elasticity, Flexural strength and She...
ABSTRACT This research dealt with the investigation of possibility of the use of the two representative seismic codes, UBC 1997, and IBC 2006, for seismic force analysis of R.C. buildings in Sudan. The theory of the seismic forces analysis was studied and presented. A R.C. building of eight storeys constructed in two sites, a very low seismic active site and a moderate seismic active site in Sudan which was analyzed by using ETABSv9.7.4 computer program. Utilizing data of the two sites, app...
In addition to the inherent advantages of an outrigger system over conventional framed structural system, damped-outrigger systems (DOS) enhance it further with its agility to resist lateral loads in high-rise buildings. Dynamic response of slender and flexible buildings with DOS induces vibration control in which twisting of core structure is restricted by shear deformation of the damper present at the end of outrigger connected by perimeter columns. In this paper, a 300 m tall core-tube typ...
ABSTRACT This research work presents the static analysis of short cylindrical shell under internal liquid pressure with various boundary conditions and aspect ratios. Improved fourth order finite difference method was employed for the analysis and a MATLAB computer program was developed based on the matrix equations and models generated from the analysis. The following boundary conditions were covered in this research; short circular cylindrical shell simply supported at both edges(s-s), sho...
Excellent mechanical properties plus to the good biocompatibility of single-walled carbon nanotubes (SWCNTs) are offering them as efficient nanodevices for delivering of nanoparticles. Due to the friction between the outer surface of the nanoparticle and the inner surface of the SWCNTs, mass weight of the nanoparticle, and the interactional van der Waals (vdW) forces between the constitutive atoms of the nanoparticle and those of the SWCNT, both longitudinal and transverse waves propagate wit...
Interaction of a moving nanoparticle with a single-walled carbon nanotube (SWCNT) is of concern. The SWCNT is simulated by an equivalent continuum structure (ECS) under simply supported boundary conditions. The moving nanoparticle is modeled by a moving point load by considering its full inertial effects and Coulomb friction with the inner surface of the ECS. The ECS under the moving nanoparticle is modeled based on the Rayleigh, Timoshenko, and higher-order beam theories in the context of th...
The potential applications of nano plates in energy storage, chemical and biological sensors, solar cells, field emission, and transporting of nano cars have been attracted the attentions of the nanotechnology community to them during recent years. Herein, the later application of nano plates from non local elastodynamic point of view is of interest. To this end, dynamic response of a nano plate subjected to a moving nano particle is examined with in the context of non local continuum theory ...
ABSTRACT The paper presents an analysis of beams on non-homogeneous elastic foundation, where the deformation is partly localized and partly continuous. The soil was modeled to be in layers, in which two layers within the soil strata were considered. The different layers of the soil have their respective sub-grade modulus k, and the entire foundation is resting on a rigid base. The formulation was achieved by imbedding a beam of known bending rigidity within the layers of the foundation. The...
A full analysis and design theories have been reviewed conducted to determine response of a buried corrugated steel structural plate culvert for four exceptional shapes as; a round pipe, horizontal ellipse, arch andlow profile arch. The select of culverts span, cover, and exceptional live load have been applied and all were have the same value. AASHTO LRFD Method has been used to measure the result of analysis and design by using manual and computer program techniques. Data collected by�...
ABSTRACT This work investigates the structural characteristics of soilcrete blocks (lateritecement blocks and laterite-sand-cement blocks) produced with locally available and affordable laterite. Scheffe’s simplex method and Osadebe’s regression theory were used to formulate mathematical models for optimisation of properties of soilcrete blocks which include compressive strength, split tensile strength, shear strength, flexural strength, Poisson’s ratio, modulus of elasticity, shea...