OBJECTIVE To compare the disinfecting efficacy of the sodium hypochlorite irrigation by root canal preparation with stainless steel hand files, taper 0.02 and nickel-titanium Mtwo files with taper 0.04-0.06. STUDY DESIGN 40 extracted human teeth were sterilized, and then inoculated with Enterococcus faecalis (ATCC 29212). After 6 day incubation time the root canals were prepared by hand with ...

AIM The aim of this study was to measure the increase in root canal surface area and canal transportation after biomechanical preparation at 1, 3, and 5 mm short of the apex with three different rotary systems in both continuous rotary and reciprocating rotary motions. MATERIALS AND METHODS Sixty freshly extracted human mandibular molars with mesial root canal curvatures between 20° and 30° w...

The purpose of the work is organization six-cylinder diesel engines (with a power 116 and 156 kW) working process with exhaust gas recirculation. following systems components were used in experimental configuration engine: Common Rail BOSСH accumulator fuel injection system an pressure 140 MPa equipped electro-hydraulic injectors 7-hole nozzle 500 mm3 hydraulic flow; direct MOTORPAL pump maximu...

in order to comparison of weeds mechanical control for sugar beet, a rotary cultivator was designed and constructed in first year, and compared with other mechanical control in second year. five treatments, included: rotary hoe cultivator, furrower cultivator, rotary cultivator, no weeding and manual weeding were compared. experiment design was random complete blocks design (rcbd) with three re...

The aerodynamic loads on a Canard Rotor/Wing vehicle are investigated using inviscid numerical simulations in order to understand the flight characteristics of the vehicle during conversion from rotary to fixed-wing flight. A series of numerical simulations at seven azimuthal rotor indices are presented covering a quarter turn of the rotor. With symmetry arguments, these simulations produce 25 ...

During the machining process of a complex rotating proÞle, numerous nonlinear characteristics of the process come into effect. It is thus difficult to control such a system efficiently. In this paper we propose a method to control such systems. We develop a direct adaptive control scheme for such processes, with a dynamic neural network as a controller. According to the idea of a direct adaptiv...

A polygon A in a configuration C is called rotary if C admits an automorphism which acts upon A as a one-step rotation. We study rotary polygons and their orbits under the group of automorphisms (and antimorphisms) of C. We determine the number of such orbits for several symmetry types of rotary polygons in the case when C is flag-transitive. As an example, we provide tables of flag-transitive ...