Electromagnetic fields in the air gap of an electric machine produce electromagnetic forces between the rotor and stator. The total force exerted on the rotor due to the eccentric rotor position is called the unbalanced magnetic pull. This eccentricity force is directed roughly over the shortest air gap. At low frequencies, the vibration amplitudes of flexural modes may be large enough to coupl...

BACKGROUND Comedones are usually found in acne and involve the seborrheic areas of the skin. Disseminated comedones can be found in other skin disorders. Flexural comedones are characterized by double orifices connected by a thin layer of epidermis that reveals the comedo content below it. To the best of our knowledge, flexural comedones have not been previously described as an entity. Our obje...

OBJECTIVES The purpose of this study was to evaluate flexural strengths, moduli, and maximum deflection of Clearfil AP-X (APX) and Ceram-X Mono (CXM) when cured with a quartz-tungsten halogen (QTH) or an LED-light (LED). METHODS Specimens were made according to ISO 4049 and cured with QTH or LED for 10, 20 or 60s. Flexural strength, modulus, and deflection were determined after 24 h water sto...

OBJECTIVE This study evaluated the influence of porcelain (VM9, VITA Zahnfabrik, Germany) thickness on the flexural strength and crack propagation in bilayered zirconia systems (YZ, VITA Zahnfabrik, Germany). MATERIAL AND METHODS Thirty zirconia bars (20.0x4.0x1.0 mm) and six zirconia blocks (12.0x7.5x1.2 mm) were prepared and veneered with porcelain with different thickness: 1 mm, 2 mm, or 3...

OBJECTIVES There has been a growing interest in glass ceramic systems with good esthetics, high fracture resistance and bonding durability, and simplified fabrication techniques using CAD/CAM. The aim of this study is to compare flexural strength before and after heat treatment of two lithium disilicate CAD/CAM blocks, IPS e.max CAD (Ivoclar Vivadent) and Rosetta SM (Hass), and to observe their...

BACKGROUND The use of composites in dental restoration has been commonly criticized, due to their underwhelming mechanical properties. This problem may be solved partially by preheating. The present research aims to determine the effect of preheating on the mechanical properties of two different classes of composites. MATERIAL AND METHODS A Silorane-based (Silorane) and a Methacrylate-based (...

Despite the large number of studies addressing the effect of microwave polymerization on the properties of acrylic resin, this method has received limited clinical acceptance. This study evaluated the influence of microwave polymerization on the flexural strength of a denture base resin. A conventional heat-polymerized (Clássico), a microwave-polymerized (Onda-Cryl) and a autopolymerizing acryl...

The aim of this study is to evaluate the flexural resistance of three types of restorative materials: compomer (Freedom), resin-modified glass-ionomer (Vitremer) and composite resin (Esthet-X), observing whether the application of bleaching agent can cause alterations of their flexural properties. Sixty samples were made using a 10 x 1 x 1 mm brass mold, and divided into three groups: G1- Freed...

This study evaluated the effect of water-bath and microwave post-polymerization treatments on the flexural strength and Vickers hardness of four autopolymerizing reline resins (Duraliner II-D, Kooliner-K, Tokuso Rebase Fast-TR and Ufi Gel Hard C-UGH) and one heat-polymerized acrylic resin (Lucitone 550-L), processed using two polymerization cycles (short cycle - 90 minutes at 73 degrees C and 1...

Two modes of flexural waves can be generated by a dipole source in an anisotropic borehole. Their velocities are related to those of the fast and slow shear waves in the formation. The particle motions and the polarization diagrams of the fast and slow flexural waves are measured in borehole models made of phenolite materials with transverse isotropy or orthorhombic anisotropy. The experimental...