Definition,calculation and application of total water potential;

In light of the fundamental principle in physics,this paper analyzes the total water potential concept built on energy viewpoint, and concludes that total water potential contains two energy forms: mechanical energy and thermal energy,which are the driving forces for water transfer and thermal dynamic processes.

The general trend of energy technology and industrial development will be effected by the following factors such as continued increasing of energy consumption on the world, energy price gradual comes down, energy production and consumption trend to a global scale, fossil energy resource abundant, cleaned and high efficiency energy demand.

The principle of total potential energy with stationary value in elastic system dynamics and the vibration analysis of train-bridge time-varying system;

Based on the total potential energy of elastic curved beams by considering the geometrical nonlinearity, the theoretic solution for the flexural-torsional buckling load of fixed-end circular arches subjected to uniform compression and bending is deduced with the Retz method, taking the effects of warping rigidity into account.

Based on the fundamental assumptions of thin walled structure,the geometrically nonlinear total potential energy was obtained by adopting an exact warping displacement of curved beam with biaxially symmetric cross section.

Species diversity of pteridophytes in the evergreen broadleaved forest in Jiulianshan National Nature Reserve of Subtropical China was analyzed based on field and plot investigation,in cluding their major composition characteristics,sum of dominance ratio(SDR),α-diversity index and β diversity index of their different communities.

The thesis expounds that the thinking inclination of the editor-in-chief has a strong effect on the planning of current events and news.