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In order to explore the production process, fire retardant properties and mechanical properties of retardant poplar plywood, this paper, with poplar veneer as testing material, centers on the manufacture of flame-retardant plywood by the use of ammonium polyphosphate flame retardant. The optimized impregnation process of veneer was explored by oxygen index method and photometry. The fire retardant properties of plywood were studied by cone calorimeter method. It was showed that: the optimized of veneer impregnated process was taking soaking temperature of 40 °C, soaking time of 0.5 h and impregnated concentration of 20%. APP flame-retardant could significantly shorten the combustion duration time of poplar plywood and greatly reduce the heat release rate, total smoke release as well as the mass loss rate, and thus obviously enhance the mass of combustion char residue, which reflected the fact that the APP flame retardant had a significant retardant effect. But the total increasing smoke emission also indicated that smoke-suppression property of APP flame retardant still needed to be improved. Through a comprehensive analysis on APP, we could see that it was a better flame retardant.

With bagasses as testing material, UF as adhesive and APP of liquid and powder as flame retardants, amount of flame retardants content, glue consumption and design density as testing factors, orthogonal experiment was conducted. Retardant and mechanical properties were tested by cone calorimeter and universal mechanical testing machine, respectively. The results showed that: with the increasing of APP adding content, curing time of UF reduced, viscosity of UF decreased and bonding strength reduced. The optimal parameters were: process of bagasse board was processed by liquid APP, the adding mount of APP was 12%, the amount of UF was 15%, density designed of board was 0.85g/cm3.

In this paper, a patch antenna with an PBG (photonic band-gap) structure was studied by FEM method, and the theory of PBG structure was introduced. The Ansoft HFSS is used for the simulation. A comparison between the conventional patch antenna and the new PBG antenna is given. It is shown that the surface waves propagating along the substrate surface can be suppressed by the periodic structure due to the influence of its forbidden band. As a result, the patch antenna based on the PBG structure has a higher gain and a wider bandwidth in comparison with the conventional patch antenna.

The chemical components from benzene/ethanol extractives of fresh Chinese-fir wood were separated and identified by GC/MS after enriched. Relative content of each component was determined by area normalization. 18 compounds representing 94.96% of the extractives were identified. The main and abundant constituents were octadecanoic acid, methyl ester(16.95%), nonadecanoic acid, methyl ester (cas) (15.23%), hexadecanoic acid, methyl ester (cas) (7.12%), hexadecanoic acid, ethyl ester (cas) (6.83%), dibutyl phthalate(6.09%), cholest-5-en-3-ol (3a)- ,carbonochloridate(5.45%), isopropyl myristate(4.52%), hexadecane (cas) (4.31%), benzene (cas) (4.09%), 3,7,11,15- tetramethyl- 2-hexadecen-l-ol(4.01%), tetradecanal (cas) (3.62%), 1,2-benzenedicarboxylic acid, bis(2-ethylhexyl) ester (cas) (3.57%), a-cedrene (3.30%), nonadecane(3.14%), 1- tridecanol (2.96%), 1,2-benzenedicarboxylic acid, bis(2- methylpropyl) ester (cas) (2.21%), and so on. The most components of benzene/ethanol extractives of fresh Chinese-fir wood are not only abundant and healthy to human, but also used as bioenergy.

Now water, adhesives and other assistants are severely wasted because the extractive of Eucalyptus wood is enriched. What's worst, water pollution becomes more serious because of the polluting extractives of Eucalyptus wood. Therefore, based on the single-factor method, the fresh E. camaldulensis shavings were treated in the sorbitic extractor and supersonic wave extractor. The extractives were analyzed by ZETA and SIZER to find out the leaching rule of nano particles from E. camaldulensis wood, hence to obtain the way to lower the negative effect of the extractives. The results were following as: (1) the regression curve showed that the extraction mass increases when the extracting time extends in the sorbitic extractor; (2) diameters of leached nano particles distribute from 37.8 to 106 nm by volume evaluating indicator, and 28.2 to 91.3 nm by number evaluating indicator in the sorbitic extractor. The particles with diameters of 4150~5560 nm, 1110~6440 nm and 4150~5560 nm are too few to test, and their volume are only 0.3%, 2.6% and 0.3% respectively, however, they can bring barrier of wood extractives on wood permeability and obstructive action of wood turpentine on pulping; (3) the volume of the particles with diameter of 28.2~78.8 nm was 80.1%, the number of the particles with diameter of 24.4~50.7 nm was 89.0%, and the volume of 190~396 nm particles is 15.2%, but its number was very less. Therefore, not only extraction mass is increased but also the grouping number of leached nano particles from E. camaldulensis is lowered in supersonic wave extractor.