objective: the aim of the present study was to compare microtensile bond strengths (μtbs) of glass fiber posts to different parts of intra-radicular dentin using conventional method and one-shot technique under different light intensities. materials and methods: twenty-eight single-rooted teeth were prepared to receive fiber posts: group 1: conventional method at light intensity of 600 mw/cm2; ...

Temperature has a significant role in many actions performed on rocks. An example would be the effect of temperature on rocks in the burial of nuclear waste, geothermal energy extraction, deep oil well drilling, and fires in tunnels. In addition, due to diurnal/nocturnal as well as seasonal temperature variations, rocks undergo a process of heating and cooling. In the present work, the effect o...

in this research, the mechanical properties of seven types of nanofilm with differing amounts of silver and silver-clay particles were studied. the elasticity of modulus, tensile strength, toughness, elongation at break, tear strength and color of nanofilms were compared with those of ordinary ldpe film. results showed that the inclusion of nano particles increased the modulus of elasticity, te...

polyvinyl ester green composites were synthesized with walnut shell powder (wsp) by in-situ polymerization technique. the green composites have been evaluated for mechanical properties such as tensile strength, tensile modulus and hardness. sliding wear loss, specific wear rate and coefficient of friction were investigated by using computerized pin-on–disc machine at normal applied loads of 20,...

Estimating mechanical properties of concrete before designing reinforced concrete structures is among the design requirements. Steel fibers have a considerable effect on the mechanical properties of reinforced concrete, particularly its tensile strength. So far, numerous studies have been done to estimate the relationship between tensile strength of steel fiber reinforced concrete (SFRC) and ot...

background and aims. polymethyl methacrylate, pmma, is widely used in prosthodontics for fabrication of removable prostheses. this study was undertaken to investigate the effect of adding silver nanoparticles (agnps) to pmma at 2% and 0.2% concentrations on compressive and tensile strengths of pmma. materials and methods. the silver nanoparticles were mixed with heat-cured acrylic resin in an a...

background and aims. although microwave irradiation has been used for disinfection of dental stone casts, there are concerns regarding mechanical damage to casts during the process. the aim of this study was to evaluate the effect of microwave irradiation on the compressive strength (cs) and diametral tensile strength (dts) of stone casts. materials and methods. in this in vitro study, 80 cylin...

Pressurized water reactor (PWR) cores operate under extreme environmental conditions due to coolant chemistry, operating temperature, and neutron exposure. Extending the life of PWRs requires detailed knowledge of the changes in mechanical and corrosion properties of the structural austenitic stainless steel components adjacent to the fuel (internals) that are inherent to such conditions. This ...

In the present work, Na+-montmorillonite nanoclay (Na-MMT) was functionalized using 3-aminopropyltrimethoxysilane (3-APTMS) as a coupling agent. The covalent functionalization of MMT was confirmed by Fourier-transform infrared spectroscopy (FT-IR). In the specimen fabrication stage, 5 wt% of pristine MMT or silane-functionalized MMT (f-MMT) were incorporated into an epoxy system and the resulta...

abstract objective: the aim of this study was to evaluate the efficacy of antibiotic-loaded bone cement in controlling local infection and in regard to its physical characteristics, elastic modulus, and tensile strength in-vitro. methods: acrylic bone cement, based on polymethylmethacrylate (pmma) was mixed with the powder form of three antibiotics, i.e., gentamicin, tobramycin, and cefuroxime ...