statement of problem: resin composites are a common type of tooth coloured restorative materials. these materials are brittle and their major shortcomings are sensitivity to flaws and defects, low tensile strength, and susceptibility to catastrophic failure.the role of home bleaching agents on the fracture toughness of resin composites using four-point bending test is scanty. objectives: to com...

0022-3093/$ see front matter 2008 Elsevier B.V. A doi:10.1016/j.jnoncrysol.2008.06.014 * Corresponding author. Tel.: +609 258 5680; fax: + E-mail address: [email protected] (G.W. Sche The Young’s moduli of a set of silica aerogels have been measured by two techniques: 3-point bending and uniaxial compression. The data found by the two methods differ strongly. The uniaxial compression test g...

in his paper the effect of ribbing in bending and tortional resisance of the box type structure is discussed . for satisfactory design of press structures . the stiffness characteristics of individual components are recognised to be of primary importance. heavy press stucures are normaly constructed in double-sided form . because of transportation and handing problems , these frames are usually...

The Multi-DOF forceps manipulator we developed has two additional DOF of bending on the tip of forceps, and provides new surgical fields and techniques for surgeons. The most remarkable characteristics of the prototype described in this paper are: 1) the small diameter and the small radius of curvature of bending; 2) the confirmation of perfect cleanness and sterilization of this manipulator. I...

The primary skeletal structure used by dolphins to generate the dorsoventral bending characteristic of cetacean swimming is the vertebral column. In the vertebral column of the saddleback dolphin Delphinus delphis, we characterize the static and dynamic mechanical properties of the intervertebral joints, describe regional variation and dorsoventral asymmetries in mechanical performance, and inv...

bending and compression strength of paulownia fortunie wood grown in educational and research forest located at shastkalate, gorgan were studied. paulownia trees were selected among five years old plantation. sampling spot was conducted following standard procedure. trees were cut into logs, which were then cut into 6 cm thickness wood blocks based on geographic directions. wood blocks were div...