objective(s): the aim of this study was to synthesis new dental nanocomposites reinforced with fabricated glass nanoparticles and compare two methods for fabrication and investigate the effect of this filler on mechanical properties. materials and methods: the glass nanoparticles were produced by wet milling process. the particle size and shape was achieved using psa and sem. glass nanoparticle...

in the present study, shearing properties of sugar cane stems were determined at five moisture content levels (46, 54, 62, 70 and 78% wb), three shearing speed (5, 10 and 15 mm min-1) and at ten positions on the stem. for measuring the shearing forces, the stems were severed by using a computer aided cutting apparatus. decrease in moisture content of stem from 78 to 46% wb led to 16.3 and 16.7%...

in saturated soils, heating induces thermal expansion of both grains and the pore fluid. lower thermal expansion coefficient of aggregates results in the increase of pore pressure and reduction of the effective stress besides subsequent volume changes due to the dissipation of pore pressure and heat transfer. dissipation of thermally induced pore pressure with time is a coupled thermo-hydro-mec...

dispersive soils are prevailent in many parts of the world, including in iran. construction of hydraulic structures on dispersive soils has created various serious problems. since it is neither economical nor justified to replace a dispersive soil with a non-dispersive one, there fore stabilization of a dispersive soil in one way or another is indispensable and unavoidable. throughout this rese...

aqueous polymer quenchants are being used increasingly in steel heat treatment industries as a substitution for conventional quenchants. by adjusting the quench parameters of the polymeric media, it is possible to achieve desirable microstructure and mechanical properties in addition to reduction in distortion and cracking. in this work, polyalkylene glycol (pag) aqueous solution was used as th...

Organic farming systems still depend on intensive, mechanical soil tillage. Frequent passes by machinery traffic cause substantial soil compaction that threatens soil health. Adopting practices as reduced tillage and organic matter retention on the soil surface are considered effective ways to control soil compaction. In tropical regions, however, the acceleration of soil organic matter decompo...

during the past two decades the use of lignocellouse fibers in reinforcing composites has attracted much research activities. in the present work, date palm fiber was used for production of composites compatible withliving environment. the fibers were pre-treated chemically to remove impurities. in order to verify and compare the effectiveness of the pretreatment methods, lignin, ash, moisture ...

gypsum found in the soil beneath the foundation of structures, specially hydraulic structures, can cause serious damage to them. the mechanical behavior of gypsiferous soils has not so far been investigated in detail except for the works of petrukhin (1993). here, it has been tried to investigate the mechanical behavior and the effect of soil being leached on settlement and strength of these ki...