Based on the study of the material dissolution mechanism,it was clear that uniform solubility and controllable solubility were the key properties of soluble materials.Dissolvable magnesium and aluminum metal material were designed. The test results of the sample show that the designed dissolution rate of a dissolvable materials is 0.184 g/h under the conditions of 1% Cl- mass fraction of the solution and a temperature of 90 ℃. The advantages and disadvantages of bridge plug structure design at home and abroad were compared, based on the concept of dissolution difference and the objective of optimizing pressure bearing, anchoring and dissolution performance, a new dissolvable bridge plug, which meet the fracturing demand of Liaohe Oilfield, was developed. The results of indoor evaluation tests show that, the fracturing ball can be dissolved in 30.0 hours under the conditions of 1% Cl- mass fraction of the solution and a temperature of 90 ℃;the maximum working pressure of the dissolvable bridge plug is 70.0 MPa, the effective sealing time is more than 12.0 hours, and the dissolution time is 16.0 days. The field test was carried out with the developed dissolvable bridge plug. During the field test, the setting and releasing operation was successful, and the soluble ball was obviously in place. The bridge plug has been dissolved after 18.0 days of spraying. The successful development of dissolvable bridge plug will provide important supports for the large⁃scale volume fracturing technology in Liaohe Oilfield.

Among the anode materials, silicon is an ideal anode material for high⁃energy and high⁃power lithium ion batteries because of its exceptionally high theoretical capacity (4 200 mA·h/g) and low operation potential (~0.4 V vs Li/Li+). However, the huge volume change of silicon anode material during Li+ insertion/extraction processes causes serious structural damage and rapid capacity decay. In this paper, the lithium storage mechanism, structure evolution process, interface reaction and dynamic behavior of silicon anode material were explored. The recent progress of surface and interface modification methods, focusing on silicon electrode surface modification, electrolyte optimization and binder development, and their applications in lithium⁃ion batteries were reviewed. Challenges and perspectives about the future development of the surface and interface control of silicon anode were proposed.

Gas field group in remote control production during typhoon, Honeywell's general control system(including industrial production control system, emergency shutdown system, fire & gas system) was interrupted, and the offshore gas field group abandoned the platform after 30 minutes.According to troubleshooting and handling by a series of questions of Honeywell's general control system, And for communication problems between gas field control systems,updating communicational devices, revising switchboard's port configurations and so on, gasfield engineers reduces data congestion between communicational devises, improves the network environment, improves the stability of the system, as for the communicational questions. This practice has good experience promotion value and high social value.

Starting with the geometry and grinding wheel topography of the grinding wheel, the grinding force was studied in the mesoscopic and macroscopic angles, according to the change law of grinding force of45^#  steel. The relationships between the grinding depth, grinding speed and grinding force were obtained from the simulation of the grinding force in the mesoscopic point of view; a grinding nephogram on the base of grinding parameters and grinding force variation diagram from the simulation of grinding force in the macroscopic angle were obtained; the research on grinding force of mesoscopic and macroscopic angles were summed to obtain correction formula of grinding force of 45^#  steel.  The result of the simulation research and the grinding force correction formula showed： Grinding force with the grinding depth increased, and the larger grinding depth was, the more obvious grinding force variation tendency was; grinding force with the grinding speed decreased, when the grinding speed exceeded a certain rate of grinding, decreasing trend of grinding force slowed down.