“新高考”背景下高中思政课“三动”教学优化策略研究

“三动”教学模式旨在通过“感知、思考、实践”三个环节的有机结合,实现对学生全面素质的培养。本文旨在探讨“新高考”背景下高中思政课教学的优化策略,着重介绍了“三动”教学模式的实践与研究。本文通过对“三动”教学的理念和实施方式进行剖析,结合现实案例分析,旨在为高中思政课的教学提供有益启示与借鉴。

Effects of Copper on the Mobility and Regeneration of Planarian (Dugesia japonica)

[Objective] A mobility measurement and a regeneration assay were conducted to explore the behavioral effects of Cu2＋ on planarian Dugesia japonica. [Method] Dugesia japonica was respectively treated with different concentrations of copper solution for 4 and 6 d, and the blank control group was set. The mobility measurement and a regeneration assay of copper ions were determined by mIC50 and rIC50 . [Result] The mobility IC 50 for adult D. japonica at 24, 48, 72 and 96 h were 86, 3.73, 3.47 and 2.61 mg Cu2＋ /L, respectively. The mobility IC50s for newborns was 2.22, 1.64, 0.87 and 0.93 mg Cu2＋ /L, respectively. Although there was no significant difference between 24 and 48 h, and between 72 and 96 h of copper exposure, Cu2＋ decreased newborns locomotor behavior in a concentration-dependent manner at sub-toxic concentrations. The regeneration IC50 of eyespots and auricles for adult D. japonica at 6 d were calculated as 0.76, 0.78 mg Cu2＋ /L, respectively. The number of eyespots and auricles regeneration in planarian D. japonica showed a concentration-dependent manner. Results showed that newborns mobility and adult regeneration assay for D. japonica in a concentration-dependent manner. [Conclusion] The results of the present study suggest that planarians can be regarded as a useful bioindicator species for toxicological studies in the future.

3D numerical study on flow structure and heat transfer in a circular tube with V-baffles

A 3D numerical investigation has been carried out to examine periodic laminar flow and heat transfer characteristics in a circular tube with 45°V-baffles with isothermal wall.The computations are based on the finite volume method(FVM),and the SIMPLE algorithm has been implemented.The fluid flow and heat transfer characteristics are presented for Reynolds numbers ranging from 100 to 2000.To generate main longitudinal vortex flows through the tested section,V-baffles with an attack angle of 45°are mounted in tandem and in-line arrangement on the opposite positions of the circular tube.Effects of tube blockage ratio,flow direction on heat transfer and pressure drop in the tube are studied.It is apparent that a pair of longitudinal twisted vortices(P-vortex)created by a V-baffle can induce impingement on a wall of the inter-baffle cavity and lead a drastic increase in heat transfer rate at tube wall.In addition,the larger blockage ratio results in the higher Nusselt number and friction factor values.The computational results show that the optimum thermal enhancement factor is around 3.20 at baffle height of B=0.20 and B=0.25 times of the tube diameter for the V-upstream and V-downstream,respectively.

Numerical Study of Air Nozzles on Mild Combustion for Application to Forward Flow Furnace

An attempt was made to extend mild combustion to forward flow furnace, such as the refinery and petrochemical tube furnace. Three dimensional numerical simulation was carried out to study the performance of this furnace. The Eddy Dissipation Concept(EDC) model coupled with the reaction mechanism DRM-19 was used. The prediction showed a good agreement with the measurement. The effect of air nozzle circle(D), air nozzle diameter(d), air nozzle number(N), and air preheating temperature(Tair) on the flow, temperature and species fields, and the CO and NO emissions was investigated. The results indicate that there are four zones in the furnace, viz.: a central jet zone, an ignition zone, a combustion reaction zone, and a flue gas zone, according to the distribution profiles of H_2 CO and OH. The central jet entrains more flue gas in the furnace upstream with an increasing D while the effect of D is negligible in the downstream. The air jet momentum increases with a decreasing d or an increasing Tair, and entrains more flue gas. The effect of N is mainly identified near the burner exit. More heat is absorbed in the radiant section and less heat is discharged to the atmosphere with a decreasing d and an increasing N as evidenced by the flue gas temperature. The CO and NO emissions are less than 50 μL/L and 10 μL/L, respectively, in most of conditions.

Numerical research on lid-driven cavity flows using a three-dimensional lattice Boltzmann model on non-uniform meshes

A lattice Boltzmann model combined with curvilinear coordinate is proposed for lid-driven cavity three-dimensional (3D) flows. For particle velocity distribution, the particle collision process is performed in physical domain, and the particle streaming process is carried out in the corresponding computational domain, which is transferred from the physical domain using interpolation method. For the interpolation calculation, a second-order upwind interpolation method is adopted on internal lattice nodes in flow fields while a second-order central interpolation algorithm is employed at neighbor-boundary lattice nodes. Then the above-mentioned model and algorithms are used to numerically simulate the 3D flows in the lid-driven cavity at Reynolds numbers of 100, 400 and 1000 on non-uniform meshes. Various vortices on the x-y, y-z and x-z symmetrical planes are successfully predicted, and their changes in position with the Reynolds number increasing are obtained. The velocity profiles of u component along the vertical centerline and w component along the horizontal centerline are both in good agreement with the data in literature and the calculated results on uniform meshes. Besides, the velocity vector distributions on various cross sections in lid-driven cavity predicted on non-uniform meshes are compared with those simulated on uniform meshes and those in the literature. All the comparisons and validations show that the 3D lattice Boltzmann model and all the numerical algorithms on non-uniform meshes are accurate and reliable to predict effectively flow fields.

Coherent Destruction of Tunneling of Bosons with Effective Three-Body Interactions

The tunneling dynamics of dilute boson gases with three-body interactions in a periodically driven double wells are investigated both theoretically and numerieally. In our findings, when the system is with only repulsive twobody interactions or only three-body interactions, the tunneling will be suppressed; while in the case of the coupling between two- and three-body interactions, the tunneling can be either suppressed or enhanced. Particularly, when attractive three-body interactions are twice large as repulsive two-body interactions, CDT occurs at isolated points of driving force, which is similar to the linear case. Considering different interaction, the system can experience different transformation from coherent tunneling to coherent destruction of tunneling （CDT）. The quasi-energy of the system as the function of the periodicaJ1y driving force shows a triangular structure, which provides a deep insight into the tunneling dynamics of the system.