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The kinetics of nitrogen absorption in Fe-Cr-Mn (Mo) alloys under 0.1 MPa nitrogen pressure and 1873K was investigated by top blowing nitrogen gas into the steel melts. A thermodynamic model of nitrogen solubility was established. Also the effect of surface active elements oxygen and sulfur on nitrogen absorption was studied. The results show that Fe-Cr-Mn (Mo) melts achieve nitrogen saturation value within 50 minutes, the nitrogen solubility increases with the content of chromium and manganese, but the experiment values of nitrogen solubility are general lower than theoretical values because of the open nitrogen gas atmosphere and high surface active elements content in the steel melts. The nitrogen absorption can be described well by a second order reaction and the interfacial reaction is restrictive step. The rate of nitrogen absorption decreases by lowering the surface reaction constant due to oxygen and sulfur in the steel melts. The effect of the surface active elements oxygen and sulfur on nitrogen absorption can be described well as .

The micro/nanofibrils of poplar could be prepared by treatment of ultrasonic. The properties of micro/nanofibrils were characterized by using scanning electron microscopy (SEM) and X-ray diffractometer (XRD). The results indicated that poplar micro/nanofibril was the same as raw fiber in chemical compositions and crystal structure. The crystallinity of micro/nanofibrils was 84.99 percent, increased by 20 percent compared to original fiber after ultrasonic crushing. The micro/nanofibril diameter was from 50 nm to 1 μm.The internal bond strength (IB) of wheat-straw fiberboard could be significantly improved by adding poplar micro/nanofibril suspension to the urea formaldehyde resin adhesive(UF),when the adding amount of poplar micro/nanofibril suspension was 15wt percent, the IB of wheat-straw fiberboard was up to 0.86 MPa.

According to two parameters combination of the material thickness and air-gap depth, from the angle of pure optimization, this paper obtained the optimal parameters of single cavity and double cavity structure by using the simulated annealing algorithm for single cavity and double cavity of aluminum foam sound absorption structure of systematically optimization design at 100-4000HZ frequency band. Finally, studying effect of increasing the number of cavity on aluminum foam sound absorption properties.

Building space cooling load affected by lots of factors,was transient, multi-dimensional and highly interactive. A model of online least squares support vector machine (LS-SVM) was established to forecast the space cooling load of building, and correlation analysis was used to find out the main influencing factors, such as, dry-bulb temperature, solar irradiance, and so on. As an example, the hourly space cooling load of an office building in shanghai was investigated. The hourly space cooling load was firstly calculated by the simulation software of DEST, and then, an online LS-SVM model was presented to forecast the load. The simulation results showed that the online LS-SVM model was effective for space cooling load prediction.