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Two tree peony species, Paeonia ostii and Paeonia rockii, from eight different provenances in China (four provenances for each species) were collected for their photosynthetic characteristics. Their diurnal variations of photosynthesis, the light- and CO2-response curves and chlorophyll content were determined. Among all eight provenances, Ziwuling P. rockii had a significantly higher average daily net photosynthetic rate, showing a superior photosynthetic capacity, followed by Fengxiang P. ostii and Xunyang P. ostii. In addition, Ziwuling P. rockii had the highest maximum net photosynthetic rates, thus, presented a strong photosynthetic potential. Furthermore, Xunyang P. ostii, Fengxiang P. ostii, and Heze P. ostii also exhibited a great photosynthetic capacity and light adaptability, which was consistent with their high chlorophyll a/b values. Taken together, Ziwuling P. rockii had the strongest photosynthetic capacity among all tested sources, followed by Fengxiang P. ostii, and Xunyang P. ostii, which are recommended to be used as seed sources for oil peony cultivation and cross-breeding.

In this article, a novel continuous twin-screw kneader was proposed. The end-cross section of the screw rotor consists of convex arcs and cycloidal curves and the rotors profiles were presented. The mixing performance of the novel twin screw kneader was simulated using finite element method (FEM) combined with mesh superimposition technique (MST). Statistical analysis was carried out for flow field using particle tracking technique to research the effect of geometry parameters and working parameters on the mixing performance. To study the dispersive mixing performance, specifically the maximum shear rate, maximum shear stress, maximum mixing index, residence time distribution (RTD) and RTD density function of tracer particles, and dispersive mixing is evaluated using the mixing index in combination with the shear stress. The results show that the changes of centre distance between female and male rotor have little influence on dispersive mixing performance, the lead of rotor has little effect on maximum shear stress and maximum shear rate, while it has an obvious effect on mixing index, cumulative RTD, and RTD density function. The rotor speed has obvious influence on mixing performance, and average residence time of material decreases greatly and the mixing ability is weakened, while the self-cleaning performance of rotor improved obviously with the increasing of rotor speed., INTRODUCTION Kneaders are closed operation units based on a self-cleaning mechanism and are widely used in blister and extrusion forming in chemical industry, as well as rubber industry or pharmaceutical [...]

The dynamic elastic-plastic behavior of a bent cantilever pipe subjected to an in-plane force pulse at its tip is described. A theoretical model based on a large deflection formulation of dynamic beam theory is described. This takes into account the plastic hardening-softening behavior which is characteristic of a pipe when it is subjected to large changes in curvature. This beam model was first formulated and applied by Reid et al. (1995b, 1996), who demonstrated that it was able to describe quite accurately the characteristics of freely whipping, straight cantilever pipes. The present paper extends this model to enable it to be applied to bent cantilever pipes and covers cases in which the bend angle is opened or closed. Previous attempts (Wang, 1991) to analyze these problems using a rigid, perfectly plastic model were not completely successful due to the inability to identify admissible modes of deformation for all circumstances. A systematic program of pipe whip tests has been carried out in UMIST on right-angled bent pipes. To illustrate the validity and use of the theoretical model, two typical cases are considered and the results compared with the experimental data extracted from high-speed films of the tests. Excellent agreement between the two is demonstrated.

A study was conducted on the hemodynamic changes associated with heatstroke in rats. The samples were exposed to a high ambient temperature to induce heatstroke. The findings reveal that a selective decline in stroke volume or ventricular depolarization due to increased plasma levels of interleukin-1 may play a key role in signaling arterial hypotension or circulatory failure in rat heatstroke.

A computational method based on a theory for turbomachinery blading design in three-dimensional inviscid flow is applied to a parametric design study of a radial inflow turbine wheel. As the method requires the specification of swirl distribution, a technique for its smooth generation within the blade region is proposed. Excellent agreements have been obtained between the computed results from this design method and those from direct Euler computations, demonstrating the correspondence and consistency between the two. The computed results indicate the sensitivity of the pressure distribution to a lean in the stacking axis and a minor alteration in the hub/shroud profiles. Analysis based on a Navier-Stokes solver shows no breakdown of flow within the designed blade passage and agreement with that from a design calculation; thus the flow in the designed turbine rotor closely approximates that of an inviscid one. These calculations illustrate the use of a design method coupled to an analysis tool for establishing guidelines and criteria for designing turbomachinery blading.