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In this study, theoretical super screen vibration analysis has been carried out to predict the dynamic characteristics of interactive waste particles. The vibrating screen is modeled of three assemblies such as screen, wastes guide, and supported screen. Then materials (or particles) of different size is to be separated by using the eccentric vibrator and classifying tilt plates. In processing separation mechanism, much lighter construction wastes (wood, Styrofoam, etc) and heavier materials are separated by staying time delay in a super screen. The design results, separation screen were able to know that small and larger particles are conspicuous difference each motion character according to trajectory particles, and small particles raise the probability in classifying tilt plates.

Using a thermodynamic model based on the generalized Landau free-energy density expansion, we investigate the influence of hydrostatic pressure on the spontaneous polarization and tilt angle of ferroelectric chiral smectic C (Sm C^*) phase near the Sm A–Sm C^* transition in a ferroelectric mesogen DOBAMBC. It is shown that the pressure dependence of the tilt angle, spontaneous polarization and Sm A–Sm C^* transition temperature (T_c) can be described in terms of four pressure-dependent Landau coefficients: two achiral coefficients a and b and two chiral coefficients Λ and d. The pressure dependence of the parameter a is due to the pressure-dependent T_c. With the increasing pressure, the stability of the Sm C^* phase decreases. A close agreement between theory and experiment is found.

We study here the tilt angle and the temperature shifts as a function of concentration for the AC* phase transition in a binary mixture, using our mean field model with the biquadratic P²θ² coupling — and also with the bilinear Pθ and P²θ² couplings. By expanding the free energy in terms of the tilt angle and polarization, the tilt angle and the temperature shift are evaluated by using the coefficients given in the free energy expansion. By employing a concentration-dependent coefficient, the tilt angle and the temperature shift are calculated as a function of concentration of 10.O.4 for the SmAC* transition in a binary mixture of C7 and 10.O.4.

Our calculated values of the tilt angle and the temperature shifts decrease as the concentration of 10.O.4 increases, as confirmed experimentally for the AC* transition in this binary mixture. This indicates that our mean field models studied here are satisfactory to explain the observed behavior of the AC* transition of the binary mixture of C7 and 10.O.4.

Tilt angle (order parameter) and the susceptibility are calculated as a function of temperature for the $\alpha$–$\beta$ transition in quartz using a Landau phenomenological model. The tilt angle as obtained from the model is fitted to the experimental data from the literature and the temperature dependence of the tilt angle susceptibility is predicted close to the $\alpha$–$\beta$ transition in quartz. Our results show that the mean field model explains the observed behavior of the $\alpha$–$\beta$ phase transition in quartz adequately and it can be applied to some related materials.

We study the steady translational fall of a homogeneous body of revolution around an axis a, with fore-and-aft symmetry, in a second-order liquid at nonzero Reynolds (Re) and Weissenberg (We) numbers. We show that, at first order in these parameters, only two orientations are allowed, namely, those with a either parallel or perpendicular to the direction of the gravity g. In both cases the translational velocity is parallel to g. The stability of the orientations can be described in terms of a critical value E_c for the elasticity number E = We/Re, where E_c depends only on the geometric properties of the body, such as size or shape, and on the quantity (Ψ₁ + Ψ₂)/Ψ₁, where Ψ₁ and Ψ₂ are the first and second normal stress coefficients. These results are then applied to the case when the body is a prolate spheroid. Our analysis shows, in particular, that there is no tilt-angle phenomenon at first order in Re and We.