Dynamic modeling and analysis of the different cavity-type hydrostatic slide turntable system
In this paper, a nonlinear oil-film force model with velocity term for hydrostatic slide system with rectangular, sector and round chamber is established respectively, by eliminating the small amount after the dimensional analysis with the help of Navier-Stokes equation, and combining with the oil-film bearing model of Hydrostatic Slide System of constant oil supply. And the turntable dynamic equations of hydrostatic slide system with different chambers are formulated consequently. Furthermore, the analysis of dynamics properties of the hydrostatic slide turntable with the same oil chamber area is investigated by numerical simulation. This research provide theoretical bases of the further studying and improving of the rest aspects property of hydrostatic oil film-turntable system.
Nonlinear film-force of journal bearing
According to the limit pressure boundary condition of a journal bearing a reynolds equation can be changed to a 2nd order nonlinear differential equation,in which variables can be separated.The expression of the film force of limited length journal bearing can be obtained by integrating the equations set.The inertia co- efficient and squeeze coefficient are defined to express the inertia force and the squeeze force of the film force respectively.The film force can explain the mechanism for film force clearly and laid the foundation for further study of the dynamic characteristics of the nonlinear rotor bearing system.
Selective and sensitive TNT sensors using biomimetic polydiacetylene-coated CNT-FETs.
Miniaturized smart sensors that can perform sensitive and selective real-time monitoring of target analytes are tremendously valuable for various sensing applications. We developed selective nanocoatings by combining trinitrotoluene (TNT) receptors bound to conjugated polydiacetylene (PDA) polymers with single-walled carbon nanotube field-effect transistors (SWNT-FET). Selective binding events between the TNT molecules and phage display derived TNT receptors were effectively transduced to sensitive SWNT-FET conductance sensors through the PDA coating layers. The resulting sensors exhibited an unprecedented 1 fM sensitivity toward TNT in real time, with excellent selectivity over various similar aromatic compounds. Our biomimetic receptor coating approach may be useful for the development of sensitive and selective micro- and nanoelectronic sensor devices for various other target analytes.