in the past 30 years, electroless nickel (en) plating has grown to such proportions that these coatingsand their applications are now found underground, in outer space, and in a myriad of areas inbetween. moreover, in order to further improve the mechanical and tribological properties of thenickel-phosphorous (ni-p) coatings, ni-p/ptfe composite coatings can be obtained, which provideseven grea...

in this research, the removal of malachite green dye from textile wastewaters using polyaniline coated onto sawdust (pani/sd) has been investigated. ammonium peroxodisulphate was used as chemical oxidant for polymerization of polyaniline directly on the surface of sawdust. the effects of some important parameters such as ph, initial concentration, sorbent dosage, exposure time and temperature o...

high performance fiber reinforced cementitious composite (hpfrcc) materials exhibit strain hardening behavior with multiple cracking under tensile loading. in this paper, experimental and parametric studies are performed to assess the influence of using hpfrcc material instead of normal concrete in reinforced concrete beams. after calibrating the experimental results, the analytical results inc...

Polymer-clay nano-composite materials, in which nano-meter thick layers of clay dispersed in polymer matrix, have generally higher mechanical properties than normal polymeric materials. A new three-dimensional unit cell model has been developed for modeling three constituent phases including inclusion, interphase and matrix. The total elastic modulus of nano-composite is evaluated.  Numerical r...

STATEMENT OF THE PROBLEM The adhesion of resin-modified glass-ionomer (RMGI) to composite resin has a very important role in the durability of sandwich restorations. Hydroxyapatite is an excellent candidate as a filler material for improving the mechanical properties of glass ionomer cement. PURPOSE The aim of this study was to assess the effect of adding micro- and nano-hydroxyapatite (HA) p...

Wood is a naturally renewable material with both continuous and isolated pore systems. Wood-composite panels have the privilege of offering a homogeneous structure to be used as constructional and structural materials. However, its nature makes it susceptible to biological wood-deteriorating agents, water absorption and thickness swelling, fire, etc. Using nano-materials are very easy in the wo...

In this paper, Eringen’s nonlocal elasticity and Timoshenko beam theories are implemented to analyze the bending vibration for non-uniform nano-beams.  The governing equations and the boundary conditions are derived using Hamilton’s principle. A Generalized Differential Quadrature Method (GDQM) is utilized for solving the governing equations of non-uniform Timoshenko nano-beam for pinned-pinned...

In the present study, fabrication and characterization of compound composite nanofibers of Polyvinyl Alcohol (PVA) with nano silver and Polyamide 6 (PA6) are demonstrated. Compound composite fibers with core-shell structure were made using co-axial electrospinning method. The shell was made up of nano silver (Ag) impregnated PVA while PA6 was the core material. These compound composite nanofibe...

In this present study, experimental work was conducted to study the effectiveness of newly innovated steel-CFRP composite (CFRP laminates sandwiched between two steel strips) as stirrups. A total numbers of eight concrete beams were tested under four point loads. Each beam measured 1600 mm long, 160mm width and 240 mm depth. The beams were reinforced with different shear reinforcements; one wit...

This paper describes analytical methods that can be used to determine the deflections and stresses in highly compliant graphite-reinforced cementitious composites. It is demonstrated that the standard transform section method fails to provide accurate results when the elastic modulus ratio exceeds 20. So an alternate approach is formulated by using the rule of mixtures to determine a set of eff...