Advanced Materials Research Vol. 413

Abstract: We researched and developed effective technology of obtaining carboxymethylcellulose from poplar wood, cotton cellulose and purified cotton lint using nonstandard equipment, developed on monoapparat method, which allows to obtain carboxymethylcellulose with high molecular mass and resistant to high temperatures during drilling in oil wells.

Abstract: In this article are shown the results of researches of development of effective composite chemical reagents based on organic and inorganic ingredients for drilling fluids, used for the drilling of oil wells. In this article will give comparative properties of local drilling fluids compared with drilling fluids used in Russia, USA.

Abstract: We developed effective composite wood-polymer materials based on poplar and produced the sliding bearings of working bodies of friction units of machines and mechanisms of cotton produced plants. The implementation of developed composite wood-polymer materials will allow significant increase of efficiency and durability of working bodies of equipment and decrease the expenses spent for bearings of cotton machines.

Abstract: This paper addresses the SMC-based adaptive wavelet-neural tracking control problem for a class of uncertain nonlinear systems. The adaptive wavelet-neural controller is designed under constrain that not all atate variables are available for measurement. A state observer is used to estimate unmeasured states of the systems. The global asymptotic stability of the closed-loop system is guaranteed according to the Lyapunov stability criterion. The simulation presented in the inverted pendulum system control indicates that the proposed approach is capable of achieving a good trajectory following performance without the knowledge of plant parameters.

Abstract: In current ACI 440.1R-06 design guideline, an environmental reduction factor (ERF) is specified to account for long-term durability of GFRP bar used in reinforced concrete structures. Such ERF factor is still lack of confidence to concrete industry prior to deliberate calibrations with in-field real time data. In this paper, a parametric study on the design of GFRP bar RC bridge deck per ACI 440 guideline is presented to investigate the stress level in GFRP bar under ultimate design loads per AASHTO LRFD Specifications. Results show that tensile stress in GFRP under ultimate design loads is always less than 25% of GFRP guaranteed tensile strength f*fu, which is much lower than the design strength per as specified in ACI 440 Guideline (i.e., 0.7 f*fu). It showed that GFRP bar RC bridge deck as designed in accordance with ACI 440 guideline could give sufficient safety margin.